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Copyright of Materialwissenschaft und Werkstoffechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metallization, a process for applying anti-corrosion coatings, has advantages over hot-dip galvanizing, such as reduced thermal stress and the ability to work "in situ". This process consists of the projection of a protective metal as coating from a wire as application material, and this wire is obtained by multi-stage wiredrawing. For the metallization process, a zinc–aluminum alloy wire obtained by this process is used. This industrial process requires multiple stages/dies of diameter reduction, and determining the optimal sequence is complex. Thus, this work focuses on developing models with the aim of designing and optimizing the wiredrawing process of zinc–aluminum (ZnAl) alloys, specifically ZnAl15%, used for anti-corrosion applications. Both analytical models and numerical models based on the finite element method (FEM) and implemented by computer-aided engineering (CAE) software Deform 2D/3D v.12, enabled the prediction of the drawing stress and drawing force in each drawing stage, producing values consistent with experimental measurements. Key findings include the modeling of the material behavior when ZnAl15% wires were subjected to the tensile test at different speeds, with strain rate sensitivity coefficient m = 0.0128, demonstrating that this type of alloy is especially sensitive to the strain rate. In addition, the optimal friction coefficient (µ) for the drawing process of this material was experimentally identified as µ = 0.28, the ideal drawing die angle was determined to be 2α = 10°, and the alloy's deformability limit has been established by a reduction ratio r ≤ 22.5%, which indicates good plastic deformation capacity. The experimental results confirmed that the development of the proposed models can be feasible to facilitate the design and optimization of industrial processes, improving the efficiency and quality of ZnAl15% alloy wire production. [ABSTRACT FROM AUTHOR]

Incremental sheet forming has emerged as an excellent alternative to other material forming procedures, incrementally deforming flat metal sheets into complex three-dimensional profiles. The main characteristics of this process are its versatility and cost-effectiveness; additionally, it allows for greater formability compared to conventional sheet forming processes. Recently, its application has been extended to polymers and composites. The following review aims to present the current state of the art in the incremental sheet forming of polycarbonate, an outstanding engineering plastic, beginning with initial studies on the feasibility of this process for polymers. Attention is given to the advantages, drawbacks, and main applications of incrementally formed polycarbonate sheets, as well as the influence of process parameters and toolpath strategies on features such as formability, forming forces, deformation and failure mechanisms, geometric accuracy, surface quality, etc. Additionally, new hybrid forming methods for process optimisation are presented. Finally, a discussion is provided on the technical challenges and future research directions for incremental sheet forming of polycarbonate and, more generally, thermoplastics. Thus, this review aims to offer an extensive overview of the incremental forming of polycarbonate sheets, useful to both academic and industrial researchers working on this topic. [ABSTRACT FROM AUTHOR]

Conventional sheet metal forming processes have problems like low formability, non-uniform strain distribution, spring back, wrinkling, etc. High velocity processes like electrohydraulic forming can deform sheets at high strain rate and have capability to tackle such problems associated with conventional forming operations to a greater extent. Forming limit diagram (FLD) characterizes sheet deformation as measure of formability. Punch stretch test (PST) can assess formability of sheet in conventional low strain rate process, but no standard method is available to determine FLD at high strain rate. So in the present work, an experimental setup has been developed to characterize sheets at high strain rate using hydraulic forming process with a 40 kJ capacitor bank. A similar corresponding standard setup for punch stretch test is also developed for comparative study of formability with respect to dome height, forming limit curve, and strain distribution. Formability of aluminum alloy AA5754 is determined at quasi-static and high strain rates, and comparative analysis is reported for whole state of strain using dog bone samples of width ranging from 10 to 120 mm. An estimate of electrohydraulic forming parameters for high strain test of the Al alloy using the given setup is also determined. Study of comparative strain distribution behavior of samples of different widths is also carried out. Comparative analysis shows that there is an improvement in formability and strain distribution behavior of the alloy deformed using EHF as compared to PST. [ABSTRACT FROM AUTHOR]

Duplex stainless steel (DSS) 2205 finds wide application in aircraft industries and for surgical implants. However, the formability of 2205 steel sheets is limited under normal conditions, requiring hot-working to enhance strain hardening at lower temperatures. Furthermore, there is a lack of research on the single point incremental forming process (SPIFP) applied to DSS 2205. Hence, the current study aims to explore the fracture characteristics of 2205 steel sheets using SPIFP, while varying several parameters such as tool type, tool diameter, speed, feed rate, and vertical step down. Optimal process parameter selection holds significant importance due to its potential for cost reduction and enhancement of quality. This choice involves determining suitable process parameters while considering multiple conflicting factors, necessitating the application of the multiple criteria decision-making (MCDM) approach. Hence, this work addresses the MCDM challenge using the additive ratio assessment (ARAS) and complex proportional assessment (COPRAS) techniques. The experiment carried out with two different forming tools such as hemispherical-ended forming tool and ball-ended forming tool, assessment carried out by varying the stated independent parameters. The dependent parameters include straight groove depth, wall angle depth, spring back, formability, and surface roughness. The SPIFP alternatives are assessed using the aforementioned two techniques, and the outcomes are subsequently analyzed. The best possible arrangement was determined using ARAS and COPRAS methods to achieve both maximum and minimum values for all the responses. This arrangement was identified with the hemispherical-ended forming tool and the specific set of process parameters: a tool diameter of 10 mm, a feed rate of 600 mm/min, a speed of 200 rpm, and a vertical step down of 0.6 mm. In 77.78% of instances, the rankings from ARAS are in agreement with the rankings from COPRAS. Notably, the lower and higher orders of rankings are the same, adding an intriguing dimension to the observation. However, the patterns of different dependent variables, influenced by the diversity of independent variables, were not consistent. These intricate mechanisms have been recognized and documented. [ABSTRACT FROM AUTHOR]

Hydroforming is a modern metal-forming process prominently used in the shipbuilding, aerospace, and automotive industries for forming lightweight, complex-shaped geometries due to their inherent process benefits. But this process faces challenges such as limited material selection, high tooling costs, and complex process control for obtaining a defect-free part with uniform thickness. Researchers are constantly innovating and advancing hydroforming technologies to overcome these limitations. This work reviews emerging tube and sheet hydroforming technologies, considering parametric effects and design considerations, particularly for micro-domain applications. Further, a wider acceptance of the hydroforming process in different industries is explored by discussing the studies that tried to improve the efficiency and quality of the hydroforming process. This study observed that better formability could be achieved in hydroforming with appropriate intermediate heat treatment, proper lubrication, the correct design of loading paths, and temperature distribution. In tube hydroforming, wrinkles, necking, and cracking observed to be largely reduced by properly selecting the internal pressure and feeding. The precise protrusion height and uniform thickness at different joint cross-sections in tube forming are found to be significantly influenced by the strain-hardening exponent, loading path, and friction coefficient. Electrohydraulic forming is found being increasingly used due to its higher productivity and lower product cost. However, further research is required to achieve complex sheet geometries with sharp corners. This research emphasizes that advanced research, artificial intelligence integration, and the exploration of alternative materials can improve the performance of the hydroforming process. [ABSTRACT FROM AUTHOR]

In this study, the thermoforming formability of continuous glass fiber-reinforced polypropylene (CGFRPP) laminates below the melting temperature were investigated. The forming limits of CGFRPP laminates were explored using flexural tests, Erichsen tests and deep drawing tests. The failure mechanism of CGFRPP in thermoforming was investigated by observing typical failure specimens using a microscope. The results show that the flexural performance and Erichsen performance are optimal at 130 °C and 2 mm/min. At 160 °C and 100 mm/min, the deep drawing performance is optimal. The restriction of fibers by the matrix is affected by the deformation temperature, and the creation of defects is affected by the deformation rate. During forming, the CGFRPP laminates undergo shear and extrusion deformations, resulting in wrinkles, delamination, and fiber aggregation. [ABSTRACT FROM AUTHOR]

Featured Application: This paper develops an innovative post-weld composite treatment process, which can significantly improve the formability of aluminum alloy tailor welded blanks compared with the traditional single post-weld treatment method. The mechanical properties and cross-sectional geometric dimensions of the fusion zone (FZ), heat affected zone (HAZ), and base metal (BM) of 6xxx series aluminum alloys are inconsistent after filler wire welding, which reduces the formability of aluminum alloy tailor welded blanks (TWBs). This paper proposes a post-weld cold rolling-solution heat treatment (PWCR-SHT) composite process, and the effects of weld excess metal, plastic deformation, and SHT on the formability of aluminum alloy TWBs are studied. The results show that the PWCR-SHT composite process eliminates the weld excess metal and internal pores, reduces the stress concentration at the weld toe, eliminates the local strain hardening behavior, and causes recrystallization in the FZ region. The cupping value of aluminum alloy TWBs using SHT is 105% of BM, in comparison, the cupping value of aluminum alloy TWBs using the PWCR-SHT composite process is 119% of BM, which is the result of the combined effect of geometric dimensions consistency and mechanical properties consistency. [ABSTRACT FROM AUTHOR]

The hybrid method, known as Incremental Sheet Hydro Forming (ISHF), is a combination of the techniques of Incremental Sheet Forming and Sheet Hydro-Forming. The primary concern identified in the incremental sheet forming formation strategy relates to the potential failure of the product due to the thinning of the sheet and subsequent springback. In response to the issue of sheet failure resulting from thinning, a revised iteration of the integrated sheet hydroforming (ISHF) method was proposed. The revised version of the ISHF process has demonstrated notable improvements in the malleability of the material. The ISHF technique entails the movement of a single ball tool along one side of the sheet's surface, while hydraulic support is applied on the opposite side through the use of pressurized hydraulic fluid. The present study sought to investigate the impact of hydraulic support on metal formability and thickness distribution. In addition, a modified variant was also considered. The experimental results are in close agreement with the predictions made by the analytical models. The strain distribution throughout the length of deformation for the sheet has been calculated. The surface quality of the products was found to be satisfactory and a preliminary simulation has been performed. This study examines the influence of process factors, specifically spindle speed (1000/1500/2000 RPM), feed rate (400/600/800 mm/min), tool diameter (8/10/12 mm), and step-down (0.2/0.4/0.6 mm), on the cone-shaped feature at the specimen of aluminum alloy A 5010. The results demonstrated that, through analysis of variance, the most influential factor in the distribution of thickness was speed. Regarding formability, the rate of change was found to be the highest at 50%. [ABSTRACT FROM AUTHOR]

Tailor weld blank (TWB) is preferred in different components of automobiles to reduce weight of the vehicle. However, TWBs have lower formability than sheets because of increased hardness and strength of weld region. Hence, in this work, detailed formability analysis of TWB of AISI304 is done and compared with as-received sheets along with microstructural correlation. Forming limit diagram for as-received sheet, TWBs are determined. Strain hardening exponent value of as-received sheet is 0.381, unweld region and weld region of TWB is observed to be 0.362 and 0.301, respectively. Numerical simulations were also done for predicting the FLC of TWB of AISI304 with the help of PAM STAMP 2 G solver. TWB showed lower formability than as-received sheets. Similarly, predicted FLD for TWB is almost coinciding with the experimental value. Similarly, optical micro-structure studies were also analysed for as-received sheet, unweld region and weld region of TWB, which showed fully austenitic structure with random grain orientations. At the same time, it was found that strain path chosen for FLD determination has a strong influence on microstructure evolution. [ABSTRACT FROM AUTHOR]

In order to understand the formability of as-received tempered commercial pure titanium grade 2 foils (CP Ti Gr2) with a thickness of 38 µm, a series of micro limited dome height (µ-LDH) tests were conducted in quasi-static speed (0.01 mm/s) at room temperature without the use of a lubricant. A technique developed at NIU was also used to create micro-circular grids (ϕ50 μm) on the as-received material. The forming limit curve (FLC) of the CP Ti Gr2 foils was obtained through the proposed µ-LDH test. For having mechanical properties of the CP Ti Gr2 foils for LS-Dyna FEA (Finite Element Analysis) simulations, a series of tensile tests in three directions were also conducted at room temperature with the same speed. The obtained FLC has been validated using a micro deep drawing case study in which both FEA simulations and experiments were conducted and compared. It has been proven in this study that the FLC obtained using the proposed µ-LDH test can be used for an extremely thin sheet-metal-forming process by the automotive, aerospace, medical, energy, and electronic industries, etc., right away for product design, forming process development, tool and die designs, and simulations, etc. [ABSTRACT FROM AUTHOR]

This study investigates the cold formability of Vanadium microalloyed steel DIN 30MnVS6 by characterizing the material's mechanical behavior at room temperature and constructing the fracture-forming limit diagram. A carefully selected set of tests was conducted to establish formability limits in terms of local deformations. Concurrently, finite element numerical analysis was employed to deepen the understanding of the influence of local stress and strain states on the material's ability to deform without fracturing. The effects of geometric conditions, lubrication, and friction on formability were thoroughly investigated. Surface stress analysis highlighted the close relationship between formability and the stress state induced by process parameters. The construction of the fracture-forming limit diagram revealed that DIN 30MnVS6 exhibits formability comparable to steels widely used in cold forging. The steel proved to be a promising option for applications in this process, providing a viable alternative in terms of formability. [ABSTRACT FROM AUTHOR]

This study thoroughly investigates the influence of anisotropy on the formability of 2024-T3 aluminum alloy sheets using advanced techniques such as digital image correlation (DIC) and Marciniak tests. A key finding is the relatively small variation in anisotropy values across different strain paths and orientations, contrasting with more significant variations reported in other studies. Tests were conducted on nine samples with various geometries to induce specific strain paths, including uniaxial, plane, and balanced biaxial strains, oriented in different directions relative to the rolling direction. The study also provides a detailed analysis of microstructural and mechanical characteristics, such as precipitate distribution and anisotropy behavior, which are crucial for understanding the relationship between microstructure and material formability. The results show that while anisotropy impacts deformation capacity, the differences in formability among the directions were minimal, with slightly greater formability observed in the diagonal direction. These findings are compared with forming limit curves (FLCs), offering an integrated view of how relatively uniform anisotropic properties influence formability. These insights are essential for optimizing the processing and application of 2024-T3 alloy in industrial contexts, emphasizing the importance of understanding anisotropy in the design of metal components. [ABSTRACT FROM AUTHOR]

The 18th International Conference on Aluminium Alloys (ICAA18) was held in Toyama, Japan from September 4 to 8, 2022, and the special issue entitled "Aluminium and Its Alloys for Zero Carbon Society" was published on Materials Transactions in February 2023 (Vol. 64, No. 2). The biennial conference covered a wide range of current trends in aluminium research; e.g. "modeling and simulation", "casting, solidification, recycling and refining", "additive manufacturing", "foams and composite materials", "mechanical properties and advanced processing", "thermomechanical processing, texture and recrystallization", "heat treatment, phase transformation and precipitation", "corrosion and surface treatments", "joining, emerging processes and multi material" and "advanced characterization". This article briefly reviews selected papers from the conference with significant experimental outcome and discussion on aluminium alloys. The author hopes that these papers are useful for all the researchers who develop next-generation technologies and materials concerning aluminium alloys. [ABSTRACT FROM AUTHOR]

Incremental sheet metal forming (ISF) is' a versatile manufacturing process carried out without the help of a die and is one of the most sought-after research areas. This research work provides a deep investigation into the impact of input parameters on formability and surface roughness. A Multipoint Incremental Forming (MPIF) tool is used in this work. Through MPIF, better surface finish and improved formability can be achieved. Also, the time required for metal forming can be reduced. The main goal in this work is to obtain improved formability and excellent surface finish in the MPIF process. Response Surface Methodology (RSM) and Multi-Objective Genetic Algorithm (MOGA) are used in this work to find the optimum combination of process parameters, including sheet thickness, vertical step depth, speed and feed rate to obtain improved formability and surface finish. [ABSTRACT FROM AUTHOR]

In pursuit of newer lightweight components, clad sheets emerge as a solution to meet the demand for automotive and aerospace applications. The present work focuses on the effect of warm forming temperature on the tensile properties, microstructural characteristics, formability, and residual stress of a two-ply clad sheet composed of SS430 and AA1050 layers. Tensile properties of the clad sheet and individual components are determined through testing of laser cut specimens as per standard at ambient and elevated temperatures (220 °C). These tensile properties are used in the material model for prediction of failure in Erichsen cupping experiments through simulations. At 220 °C, the yield and ultimate tensile strengths of clad sheets are found to decrease by approximately 10% and 18%, respectively, but ductility is observed to increase by almost 5%. Electron backscatter diffraction analysis is done to measure and evaluate the microstructural characteristics of the clad material after the tensile deformation at both temperatures. The kernel average misorientations measured from electron backscatter diffraction show that the transition layer retained its integrity during the plastic deformation, whereas the number fraction at peak misorientation values has risen substantially on either side of the transition layer, i.e., on the steel and aluminium layers. The pole figure maps indicate a weak texture of the AA1050 layer, but a stronger texture of the SS430 layer after warm forming than after forming at ambient temperature. The cupping experiments are performed to assess the formability of the clad and individual layers, at two different temperatures. To study the effect of each layer during forming, two possible cases of sheet placements are investigated; i.e., in the first case, the SS430 is on the outer side, and AA1050 is in contact with the punch, whereas in the second case, it is the opposite. The clad sheet shows better formability when the steel layer is on the outer side of the dome. The formability of the clad sheet is observed to increase by 15% at the warm forming temperature. The predicted simulation results are in good agreement with the experimental results. In order to investigate the effect of temperature on the residual stress, the variation of stresses was also determined and mapped on the tested samples across the dome after forming at ambient and warm temperatures. The residual stress across the dome of the tested samples after the warm forming is significantly reduced compared to that of the samples tested at room temperature. The favourable tensile properties, microstructural characteristics, and reduced residual stress at elevated temperature indicate better formability of the clad sheet with good bond integrity at warm forming temperature. [ABSTRACT FROM AUTHOR]

In single point incremental forming (SPIF), a technical challenge is to form multi feature parts, particularly those with unique structures. In response to this issue, a new process combining hydraulic bulging and SPIF is presented for the mouldless manufacture of multi-featured parts with sharp structures in a single clamping. In the first phase, hydraulic bulging is performed on the initial sheet to obtain a domed shell. In the second phase, local areas of the domed shell are subjected to SPIF with the assistance of hydraulic supports to achieve the concavo-convex features. In the third phase, the convex features are subjected to SPIF with the assistance of hydraulic bulging to achieve conical features. Simultaneously, the influence of hydraulic pressure on geometric accuracy, strain distribution, and forming mechanism is compared at different forming stages. The feasibility of the novel process can be verified through successful FEM and experiment of multi-feature parts. [ABSTRACT FROM AUTHOR]

In order to enhance the formability and ridging resistance of Sn microalloyed ferritic stainless steel (FSS), an investigation was conducted on the texture and microstructure evolution, as well as formability and surface ridging of Sn microalloyed FSS at various hot rolling finishing temperatures (HRFTs). This study employed x-ray diffraction, optical microscopy, electron backscattering diffraction, tensile testing, and surface roughness measurement techniques. Hot-rolled sheets with HRFTs of 940, 870, 800, and 730 °C were subjected to annealing at 950 °C for 5 min and cold rolling at a reduction of 80%. Subsequently, they were annealed at 900 °C for 2 min. The research indicates that decreasing the HRFT has a positive impact on reducing {001} <110> grains and its texture intensity. Additionally, it leads to microstructure refinement and intensification of <111> //ND (ND: normal direction), thereby improving formability and resistance against ridging. When the HRFTs are within the range of 940–730 °C, the final sheet with an HRFT of 800 °C exhibits optimal formability and surface quality due to the formation of fine recrystallized <111> //ND grains with a sharp texture intensity. In comparison to the final sheet produced through conventional hot rolling with an HRFT of 940 °C, the average r value for the final sheet with an HRFT of 800 °C is increased by 19.4%, while the ridging height is reduced by 46.5%. This demonstrates the significance of reasonable optimization of the hot rolling process in enhancing the formability and ridging resistance of Sn microalloyed FSS. [ABSTRACT FROM AUTHOR]

High-strength materials are essential for applications in the structural industry. However, their limited formability restricts broader industrial use. This study proposes a novel methodology to achieve an excellent combination of formability and strength. Surface heterostructuring through laser treatment induces local austenitization on the as-rolled martensitic stainless steel. The resultant bendability was significantly improved, enabling its bending to ∼180° folding while maintaining high tensile strength. Consequently, the present surface heterostructuring suggests achieving the superior combination of strength and formability by tailoring the microstructure specifically to forming. This surface heterostructuring will explore the empty area of the formability-strength relationship. [ABSTRACT FROM AUTHOR]

This paper delves into the formability of material deposited by wire arc additive manufacturing. It presents a novel dieless Nakajima testing procedure that offers a practical solution for obtaining strain loading paths up to failure directly from the deposited material without the need for extracting sheet blanks. The procedure involved machining a region of the deposited material to the desired shape and thickness and using a press to drive and control the movement of a hemispherical punch. The test was designed using finite element modeling, and its effectiveness in obtaining the required strain loading paths directly from the deposited material was verified through experimentation with digital image correlation. Importantly, this novel test eliminates the need for the special-purpose tool setup required in conventional Nakajima sheet formability tests, thereby simplifying the overall testing process. [ABSTRACT FROM AUTHOR]

Concurrently improving the formability and post-formed strength of Al-Zn-Mg alloy sheets is crucial for producing high-strength parts with complex shapes. A novel process of aging warm-forming (AWF) to form solution heat-treated and water-quenched aluminum alloy sheets is proposed in this paper. The as-quenched AA 7075 sheet was first pre-aged and then formed at the desired temperature. The automotive paint–bake process was then utilized as the second aging step to achieve the target strength of the formed part. Additionally, the post-formed strength and warm formability of specimens under the AWF process conditions, as well as the warm-forming of various heat-treated Al-Zn-Mg alloy sheets proposed in previous studies, were compared through tensile and limit dome height tests. Precipitate characteristics of specimens subjected to different warm-forming process conditions were examined to understand their impact on warm formability. The warm formability of Al-Zn-Mg alloy sheets was significantly enhanced, and the post-formed strength achieved was more than 90% of the strength of as-received AA 7075-T6 sheets under the AWF process condition. The results demonstrated the feasibility of this novel AWF process to manufacture Al-Zn-Mg alloy stamped parts for improved spring-back, formability, and good overall post-formed strength. The results also indicate that microstructural characteristics in Al-Zn-Mg alloy sheets under different warm-forming process conditions have a noticeable influence on warm formability and final mechanical properties. [ABSTRACT FROM AUTHOR]

Sheet metal formation plays a cost-effective and significant role in the fabrication of automobile components. Typically, a forming limit diagram (FLD) is used to determine the strain limit of the material fracture during hot forming. In this study, the Erichsen cupping test is conducted on an Al(7075) sheet at 300, 350, 400, and 450 °C to determine the FLD. The results demonstrate the displacement increases with increasing temperature and load, and it is decreased at 450 °C. Finite element analysis (FEA) of the Erichsen cupping test of the Al sheet is performed with the damage theory using ABAQUS software, and the results are compared with the experimental results. To minimize errors in the Finite Element Analysis (FEA), simulations were conducted by applying the fracture energy value ( G f ). It was observed that the displacement increased in the load–displacement curve as the fracture energy value ( G f ) increased at all temperature values. Additionally, as the G f value increased with temperature, the energy absorption capacity until fracture also increased. [ABSTRACT FROM AUTHOR]

In recent years, significant attention has been garnered by Tailor Rolled Blanks (TRBs), especially within the automotive industry, attributed to their unique performance characteristics, defined by varying thickness profiles. Nonetheless, the inherent structural complexities of TRBs have led to non-uniform deformation during forming processes, thereby compromising elongation and formability. In this study, an exploration into the deformation of TRBs under uniaxial tensile conditions is elucidated, centering specifically on TRBs transitioning from a thickness of 1–2 mm over a 100 mm span. An assessment of the properties of TRBs following partial annealing is conducted, and mechanisms responsible for thickness variations and the revelation of intrinsic mechanical traits are identified through microstructural examinations. Exploration of the mechanical behavior of TRBs under tension is undertaken, and a methodological approach for optimizing the distribution of mechanical properties is proposed. Validation is achieved through the employment of finite element models, showcasing a performance improvement in the optimized TRBs, with uniform elongation rates surpassing those of non-optimized TRBs by up to 197%. Moreover, an outperformance of uniform-thickness materials by up to 51% is exhibited by the optimized TRBs. These insights are anticipated to bolster the application and efficiency of TRBs across various engineering sectors, aligning coherently with the intelligent design and advanced materials implications within the realm of mechanics and materials in design, as spotlighted by "The International Journal of Mechanics and Materials in Design". This exploration intricately intertwines mechanics, material engineering, and intelligent design, offering a comprehensive view that stands to fortify the symbiotic relationship between advanced materials and the design process. [ABSTRACT FROM AUTHOR]

Cupro–nickel alloy of 70/30 grade was experimented for its formability by SPIF tests, namely straight groove test and wall angle test using a ball attached tool, to emphasize the concern on formability and surface roughness. Two different types of ball were used, one ball was used in polished form and another one was surface-textured using Nd-Yag laser. The cupro–nickel alloy has excellent corrosion resistance and popularly used in marine environments. In this research, an attempt has been made to study the formability when using Chrome steel laser ablated ball. The results concluded that Chrome steel laser ablated ball with oil as lubrication has avoided the occurrence galling and at the same time improved the formability. When experimenting with chrome steel polished ball, the tool and sheet contact is high and the lubricating oil will be less and it is causing the sheet to get heated. The dimples on the ball's surface made by the laser retain more lubricating oil and thereby decreasing the friction which eventually leads to the delayed fracture. It is found that the formability was increased by 16% in straight groove test, 4.8% for wall angle test and surface roughness values were decreased by 1.4%. [ABSTRACT FROM AUTHOR]

Heat-assisted Incremental Sheet Forming (HA-ISF) is a viable forming technique that uses the heat-source to form the sheet materials incrementally and progressively. The hard-to-form sheet materials may be formed effectively using the HA-ISF method which are otherwise difficult to form at the room temperature. HA-ISF may enable the greater formability of the formed sheet-parts and reduce the required forming forces for fabricating the sheet components. These possibilities have motivated the researchers to explore various aspects of HA-ISF and the effects of process factors on the various outcomes. In this review article, various dimensions and methods of this emerging technique of sheet forming have been explored. Each method of HA-ISF has been studied against the hard-to-form materials to establish a trend on the outcome like forming force, surface roughness and formability. The capabilities of these methods of warm forming have also been discussed for the hard sheet materials along with the mechanisms of the obtained results. Results shows that the nature of materials and the mode of heating the sheet during the forming process can affect the formability, surface roughness and the required deforming loads effectively. An attempt has also been made by the authors for providing and establishing the criteria to estimate the deforming loads that are required to deform the sheet material by using the analytical and predictive modelling approach. Available analytical models show difficulty in the prediction of the input parameters for desired output parameters. While the development of numerical models is very time-consuming and has significant deviation in result for the upper range of input parameters due to variation in material properties with varying temperature. Whereas, empirical modelling can be a viable approach to predict the HA-ISF process. In addition, various applications of the HA-ISF have also been discussed for streamlining this novel technique for industries to produce customized products from hard-to-form materials. Results also shows that the HA-ISF process is efficient for increasing the formability of hard sheet materials and for reducing the required deforming loads. Achieving the better dimensional accuracy and good surface finish is still the challenge in HA-ISF and researchers may focus on these areas for enhancing the capability of this technique of warm forming. [ABSTRACT FROM AUTHOR]

Copyright of Syntax Idea is the property of Ridwan Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Origami patterns play a critical role in the field of soft and reconfigurable robotics. The revolved body formed by waterbomb units is also widely used in robot design. The kinematic model plays a key role in understanding motion characteristics and is vital for dynamic modeling and control of robots based on origami. However, while the deformation of origami patterns is well-studied on the finite element level, the assembly of rigid origami patterns is rarely explored on the kinematic level. Therefore, we propose a chain-like assembly method for constructing revolved bodies using rigid waterbomb units, ensuring crease status unalternation, collision avoidance, axis existence, and seamless assembly. We explore the formability of waterbomb units and investigate the resulting revolved body with some layer and column numbers of waterbomb units. Results demonstrate that increasing the number of columns does not necessarily provide more space for building layers. Additionally, they reveal boundaries of the layer and column numbers for constructing the revolved body and highlight the impact of the aspect ratio and configuration of the waterbomb units on the formability of the revolved body. This method can provide insights for origami-based robot research and can be extended to model other origami patterns. [ABSTRACT FROM AUTHOR]

A positioning grid is a key clamping structure for fixing the transverse and axial positions of fuel assemblies in nuclear reactors, and it is generally prepared by the transverse stamping of a Zr-4 sheet. However, the texture formed in the processing process of Zr-4 sheets can affect formability, resulting in cracking in the stamping process. Therefore, the relationship between the formability of Zr-4 sheets and the normal Kearns factor (Fn) of basal texture was studied in this paper. The results showed that the Zr-4 sheet with an Fn equaling 0.720, prepared by an isobaric reduction rolling process, would crack in the stamping process. To avoid the cracking during stamping, the formability improvement of Zr-4 sheets based on texture optimization was discussed. By using the finite element model (FEM) and a visco plastic self-consistent (VPSC) model coupled simulation, the relationship between the initial textures and formabilities of Zr-4 sheet is established. It is found that the hardening exponents (n) decreased with increasing Fns in VPSC simulations. Meanwhile, as the Fn increases, cracks are prone to occur at the bottom corner of the stamped sheet in finite element simulation. Given the results from FEM and VPSC simulations, it is proposed that the Fn should be controlled to be less than 0.7 for preventing cracks in the sheet during stamping. Additionally, a new rolling process named non-isobaric reduction rolling was designed in which the Fn of the Zr-4 sheet is successfully reduced to 0.690. The stamping results indicate that the sheet is free of cracks under an Fn of 0.690. Therefore, texture optimization with the proposed rolling process can improve the formability of Zr-4 sheets, which effectively solves the cracking problem of Zr-4 sheets. [ABSTRACT FROM AUTHOR]

This paper is focused on improving material formability in hybrid wire-arc additive manufacturing comprising metal forming stages to produce small-to-medium batches of customized parts. The methodology involves fabricating wire arc additive manufactured AISI 316L stainless steel parts subjected to mechanical and thermal processing (MTP), followed by microhardness measurements, tensile testing with digital image correlation, as well as microstructure and microscopic observations. Results show that mechanical processing by pre-straining followed by thermal processing by annealing can reduce material hardness and strength, increase ductility, and eliminate anisotropy by recrystallizing the as-built dendritic-based columnar grain microstructure into an equiaxed grain microstructure. [ABSTRACT FROM AUTHOR]

In this study, the compositional design of high-formability, high-bake-hardening Al–Mg–Zn-Cu-based aluminum alloys was carried out, and process conditions were established to secure mechanical properties under harsh conditions for Al–Mg–Zn-Cu-based alloys. Using JMatPro13.0 for precipitation phase simulation, the optimal pre-aging temperature and time of the design composition were selected. Through the introduction of pre-aging, it was confirmed that no over-aging phenomena occurred, even after bake-hardening, and it was confirmed that it could have mechanical properties similar to those of test specimens subjected to traditional heat treatment. Through DSC (Differential Scanning Calorimetry) and TEM (Transmission Electron Microscope) analyses, it was found that pre-aging provided sufficient thermal stability to the GP (Guinier–Preston) zone and facilitated transformation to the η'-phase. In addition, it was confirmed that, even under bake-hardening conditions, coarsening of the precipitation phase was prevented and number density was increased, thereby contributing to improvements in the mechanical properties. The designed alloy plate was evaluated as having excellent anisotropy properties through n-value and r ¯ -value calculations, and it was confirmed that a similar level of formability was secured through FLC (Forming Limit Curve) comparison with commercial plates. [ABSTRACT FROM AUTHOR]

Sheet metal forming belongs to that category of metal forming operations wherein flat metal sheets are plastically deformed to achieve the necessary product. Forming can be performed under compressive, tensile, bending and shearing conditions. There exists a wide array of forming operations utilizing different techniques, but with introduction of computers there has been a surge in the flexibility of manufacturing processes. With a growing need of complex designs in industry at low cost, the spotlight is now on incremental sheet forming (ISF). The ability to form non-symmetrical parts without the requirement of costly dies gives ISF an edge over other sheet forming processes. Process flexibility and higher formability are other aspects which makes ISF an attractive venture for manufacturing. In the last decades, sizeable amount of work has been done in this field to make it commercially viable; especially in automobile, aerospace and defence sectors. The present paper recapitulates the variety of research carried out in the concerned area in chronological fashion and discusses the areas where more attention is required. [ABSTRACT FROM AUTHOR]

The study investigates the deep drawing process for bimetallic sheets formed by bonding dissimilar metals (AA1100 aluminium alloy and C36000 brass) with epoxy-based adhesive. Experimental exploration of process parameters, including blank diameter, stacking sequence, lubrication, and strain rate, was conducted to analyse their impact on load–displacement behaviour and thickness strain distribution. Additionally, the study assessed fracture susceptibility, material flow characteristics (tearing and wrinkling), and the requisite drawing force for the bonded specimens. Results indicate enhanced formability and mechanical properties in bonded sheets compared to individual metal sheets, demonstrating the potential advantages of this approach. The bonded sheets demonstrated improved formability and mechanical properties compared to individual metals. Notably, the maximum drawing force for the bonded sheet (170 mm diameter) significantly increased to 24.2 kN, surpassing individual sheets by 69.85% for AA1100 and 40.54% for C36000. The analysis identified a vulnerable region (12–15 mm from the centre) under maximum risk of failure and consistent deformation patterns in samples with varying diameters and lubrication, providing valuable insights into the behaviour of bonded bimetallic sheets in deep drawing. [ABSTRACT FROM AUTHOR]

Different ageing treatments have been developed to achieve targeted properties in aluminum alloys through altering microstructures. However, there is a lack of understanding regarding the effect of ageing treatments on the formability of these alloys. In this study, we employed crystal plasticity finite element (CPFE) modeling, in conjunction with the Marciniak-Kuczynski (M-K) approach, to investigate the effects of ageing treatments on the mechanical properties and formability of AA6061 aluminum alloy. The as-received sheet was in the T6 heat treatment state, which was subjected to artificial ageing and pre-ageing, respectively, to achieve two age-hardened alloys with modified precipitation states. The microstructures and crystallographic textures of the three alloys were measured using the electron backscattering diffraction (EBSD) technique, and uniaxial tensile tests were performed along the rolling direction (RD), transverse direction (TD), and diagonal direction (DD, 45° to the RD) for each alloy. The forming limit curve (FLC) of the as-received alloy was determined using the Nakazima test. The dependence of mechanical strength, tensile ductility, and work-hardening behavior on the ageing treatments was clarified. Then, the tensile test results were utilized to calibrate the modeling parameters used in the CPFE model, whereas the FLC predictability of the developed model was validated with the experimental one. In the formability analysis, the effects of the ageing treatment on the FLC exhibit a notable dependency on loading paths, and the pre-aged alloy exhibits better formability than the other two at the plane strain tension state, thanks to its high work-hardening levels. In addition, the deformed textures along the different loading paths and the effects of the initial texture on the FLC are also discussed. [ABSTRACT FROM AUTHOR]

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The demand for rapid prototyping techniques has been increasing in the field of automotive for the manufacturing of various parts with dissimilar shapes. In the present work, experimental and numerical investigations have been performed on an automotive-grade DP steel using an incremental sheet forming process at Room Temperature (RT) and 400°C. Various formability parameters such as fracture forming limits, limiting wall angle, forming forces, thickness distribution, and geometrical accuracy have been analysed. The fracture limits of the material are evaluated by forming varying wall angled conical (VWACF), and pyramidal (VWAPF) frustums. The fracture limits of the material formed at 400°C have been found to be 14.06% higher compared to room temperature fracture limits. The limiting wall angles for VWACF and VWAPF are found to be 70.73° ± 1.41° and 67.97° ± 1.35°, which are also higher than the formed constant wall angled frustum. The forming forces measured from experimental and FE simulations are in good agreement with the predicted forming forces from Arene's equation. The minimum thickness obtained from experimental and FE simulations are in good agreement with each other with an absolute error of less than 4.5% and 7% for VWACF and VWAPF. [ABSTRACT FROM AUTHOR]

The paper reports the deformation behavior of single point incremental formed part with sheet oscillation. Single point incremental forming is an emerging manufacturing technology. This technology provides the competition to the other innovative technologies such as electric-assisted manufacturing, hydroforming, high-speed forming, etc., to produce the lightweight and highly deformed components. Single point incremental forming is the die-less sheet metal forming process in which the single point tool incrementally forces any single point of sheet metal at any processing time to undergo plastic deformation. In single point incremental forming, the part stays fixed and the tool pin makes the planar and downward motion to shape the part. It has several advantages over the conventional process such as high process flexibility, elimination of die, complex shape, and better formability. Previous literature provides enormous research on the formability of metal during this process, process with various metals and hybrid metals, the influence of various process parameters, but research on the deformation behavior of the part through the oscillation of the tool was limited. In this paper, the single point incremental forming was simulated on ABAQUS finite-element software. The spiral tool path was studied. First, the part was formed without oscillation. Then the oscillation of the sheet with the help of a die and blank holder was set with a frequency to deform the part. The variation of frequency and amplitude was also studied. The formability of the part was analyzed and compared. The deformation, profile shape, strain path, thickness, and force requirement were analyzed and presented. It was found that with lower cycles the maximum stress increases with an increase in amplitude. Also, with an increase in the number of cycles the achieved strain values were lower as compared to the no oscillation case for the same cup height and thus higher deformation is possible with oscillation. [ABSTRACT FROM AUTHOR]

Tube hydroforming (THF) is an unconventional manufacturing technique that uses pressurized fluid in place of conventional punches to deform the tubular blank into the desired shape. In THF process tubular blank is deformed it into the final shape by applying fluid pressure mostly by water using water intensifier through axial punches. Tube hydroforming is mainly used to produce hollow components using tubular blank which find applications in automobile industry, particularly for exhaust systems. The formability of Austenitic stainless steel tubes as function of microstructure is not focused much in literature. Hence, in this study, formability of Austenitic stainless steel tubes is studied as a function of boundary conditions and bulge width (L/D ratio) and correlated with microstructure. Microstructure resulting in axial feed condition showed better formability than microstructure resulting in fixed feed condition. Similarly, formability and fracture behavior of tube predicted with finite element-based simulation using PAMPSTAMP 2G solver found results, particularly bulge height and fracture location are in good agreement with experimental values. The observed fracture mode noted was ductile both for axial feed condition and fixed feed condition as the fracture consists of voids and micro voids. Fracture location was in base metal just, besides, weld line for axial feed condition and fracture location was in base metal which is little away from weld line for fixed feed condition. [ABSTRACT FROM AUTHOR]

The effectiveness of local laser heat treatment technology to enhance the in situ formability of steels and aluminum alloys has already been widely acknowledged for the one-step forming of components with simple shape geometries. The present study demonstrates that this technology is also able to significantly improve the formability of a complex shaped multi-forming industrial part. An industrial grade advanced-high strength Dual-Phase DP1000 steel is used to analyze the multi-forming of a complex part to determine the most appropriate local laser heat treatment parameters and optimize in situ softening by correlating yield strength, ultimate tensile strength, elongation at fracture, strain hardening exponent and instantaneous strain hardening with local temperature dynamics during the laser treatment. Additionally, numerical simulation analysis using Autoform software is carried out to validate the selected heat affected zone and the in situ softening, ensuring that they are appropriate for improving the formability of the industrial part. These findings are then expanded to study the experimental forming of five in situ laser heat treated models, followed by comparative analysis with a benchmark. This study provides an insight and fundamental guidelines to perform in situ laser heat treatment on complex industrial parts leading to the production of the industrial multi-formed component with optimized formability. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Friction is one of the main phenomena accompanying sheet metal forming methods, affecting the surface quality of products and the formability of the sheet metal. The most basic and cheapest way to reduce friction is to use lubricants, which should ensure the highest lubrication efficiency and at the same time be environmentally friendly. Due to the trend towards sustainable production, vegetable oils have been used in research as an alternative to petroleum-based lubricants. The analysis of friction in sheet metal forming requires an appropriate tribotester simulating the friction conditions in a specific area of the sheet metal being formed. Research has used a special strip drawing tribometer, enabling the determination the value of the coefficient of friction in the blankholder zone in the deep drawing process. Quantitative analysis of the friction phenomenon is necessary at the stage of designing the technological process and selecting technological parameters, including blankholder pressure. This article presents the results of friction testing of 1.0338 (DC04) steel sheets using a strip drawing test. The experimental tests involved pulling a strip of sheet metal between two countersamples with a rounded surface. The tests were carried out on countersamples with different levels of roughness for the range of contact pressures occurring in the blankholder zone in the deep drawing process (1.7–5 MPa). The values of the coefficient of friction determined under dry friction conditions were compared with the results for edible (corn, sunflower and rapeseed) and non-edible (Moringa, Karanja) vegetable lubricants. The tested oils are the most commonly used vegetable-based biolubricants in metal forming operations. Multi-layer artificial neural networks were used to determine the relationship between the value of the contact pressure, the roughness of the countersamples, the oil viscosity and density, and the value of the coefficient of friction. Rapeseed oil provided the best lubrication efficiency during friction testing for all of the tested samples, with an average surface roughness of Sa 0.44–1.34 μm. At the same time, as the roughness of the countersamples increased, a decrease in lubrication efficiency was observed. The lowest root mean squared error value was observed for the MLP-4-8-1 network trained with the quasi-Newton algorithm. Most of the analysed networks with different architectures trained using the various algorithms showed that the kinematic viscosity of the oil was the most important aspect in assessing the friction of the sheets tested. The influence of kinematic viscosity on the value of the coefficient of friction is strongly dependent on the surface roughness of the countersamples. [ABSTRACT FROM AUTHOR]

In this paper, two advanced sealing methods are proposed to enhance the formability of aluminium alloys in the tube hydroforming process. These methods are aimed at omitting friction force at the contact area between the tube and the die in the feed region and facilitating the material flow to the deformation region. The advanced sealing methods are numerically and experimentally examined against the conventional sealing method by conducting the free bulge test on AA6063 aluminium tubes. The deformation mechanics are deeply analysed in the principal strain space to identify the influence of the sealing methods on deformation paths. In addition, the effectiveness of the advanced sealing methods is evaluated under different lubrication conditions and contact lengths in the feed region. Results show that in the advanced sealing methods compared to the conventional one, the thickness in the feed region does not increase and the necking occurs in larger in-plane strains, leading to a higher bulge height. Results also allow concluding that a higher bulge height is formed using the second advanced sealing method, in which the tube is pressurized from both sides in the feed region. Thus, the advanced sealing methods are recommended for tube hydroforming of aluminium alloys with low formability. [ABSTRACT FROM AUTHOR]

This paper presents a new methodology to determine the formability limits by local buckling in thin-walled metal tubes that is an extension of a method that was earlier developed by the authors to characterize wrinkling in metal sheets. The method consists of subjecting a set of rings with different lengths extracted from the tubes to axial compression and combining experimental measurements with finite element modeling to determine the critical in-plane surface strains at the onset of buckling. Digital image correlation is used to track the experimental evolution of the in-plane strains with the normalized height of the plastic hinges and to validate the finite element model for subsequent utilization in the determination of the critical strains at the onset of buckling. Results show the effectiveness of the proposed methodology to obtain, for the first time ever, the formability limits by local buckling of thin-walled tubes in both principal strain and effective strain versus stress triaxiality spaces. [ABSTRACT FROM AUTHOR]

The rolling process is crucial in the process design for achieving good formability of ferritic stainless steel. A comparison is made between hot rolling and cold rolling, and the influence of reduction distribution between hot and cold rolling on the evolution of microstructure and texture is discussed. The results indicate that the partitioning of a high cold-rolling reduction rate is better than the hot rolling in terms of microstructure and properties. With increasing thickness reduction via cold rolling, {223}<110> component in cold-rolled sheets exhibits a progressive strengthening, while {111} <121> component becomes more intense and the degree of deviation from the ideal γ-fiber axis is weakened after annealing. The increase in cold deformation refines the microstructure and increases the fraction of <111> //ND-oriented grains. Therefore, ferritic stainless steels with higher cold-working render an excellent combination of strength and formability. [ABSTRACT FROM AUTHOR]

The article discusses the influence of heat treatment and metal forming parameters on formability and the structure of the AZ91 cast magnesium alloy. The aim of the article is to determine the optimal parameters of homogenization and plastic deformation of sand castings made of the AZ91 alloy in order to improve their properties and structure. In this study, sand castings made from the AZ91 alloy were examined. In the first stage, the castings were homogenized at: 385 °C, 400 °C, 415 °C and 430 °C with argon as a shielding gas for 24 hours and then quenched. Subsequently the upsetting tests were conducted at 380 °C; 400 °C; 420 °C; 440 °C for two deformation values: e = 0.7 and e = 1.1. After upsetting, the samples were water- and air-cooled. At this stage, a visual assessment was made and samples without cracks were subjected supersaturation at 415 °C for 6 h, and artificial aging at 175 °C for 24 h. Vickers hardness tests and microstructure assessment were carried out, at individual stages of testing. Based on the results obtained from the upsetting, structure and hardness tests, the most favorable homogenisation and plastic deformation conditions were determined for AZ91 alloy sand castings. The best results are achieved by homogenizing sand castings at 415 °C for 24 h. Among the tested parameters for conducting metal forming processing in the range of 380-440 °C and deformation values: e = 0.7 and e = 1.1, forging of sand-cast AZ91 magnesium alloy at 420 °C and deformation of e = 0.7 with water cooling seems to be the most favourable. The final heat treatment applied after the deformation process consists of supersaturation at 415 °C for 6 hours water quenching as artificial aging at 175 °C for 24. This combination of heat and plastic treatment parameters of castings allows for improvement of the structure and properties of sand castings made of the AZ91 alloy. [ABSTRACT FROM AUTHOR]

Background: The evaluation of the formability for aluminum alloy under complex loading conditions is particularly significant. Based on the characteristics of conveniently achieving multiple strain path states, the cruciform specimen has been widely used in the experiment of evaluating formability. But there is no general specimen design scheme to realize proportional strain path history in initial fracture point. Objective: This paper was aiming at obtaining the equi-proportional strain path history and exploring the ultimate fracture strain of AA5052 aluminum alloy sheets under the equi-biaxial tension. Methods: Firstly, two cruciform specimen schemes suitable for 1.2 mm sheet materials were proposed. The strain localization characteristics were estimated and thinning critical value in the central region was determined by simulations. Subsequently, through the 3D digital image correlation (DIC) test system, the strain path history of the initial fracture point was obtained. Finally, the fracture morphology characteristics were observed through SEM. Results: The results showed that the initial fracture point could be located in the center of the specimen in both designs (Design-straight and Design-flaring). The specimens with slits showed a smaller strain gradient existed in the central region. Meanwhile, the initial point of fracture was closer to the equi-biaxial tensile strain path, and the strain limit was larger. Conclusions: The two design methods could optimize forming limit value and realize the equi-proportional strain path history in central fracture point. The Design-straight and Design-flaring was more suitable for the AA5052-O and AA5052-H material respectively. It was related to the local stress concentration effect of the material. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: This paper aims to optimize the single-point incremental forming process variables for realizing higher formability in Inconel 625 components and to plot the forming limit diagram for Inconel 625 aviation-grade superalloy. Design/methodology/approach: The formability of Inconel 625 components has been measured in terms of major strain, minor strain and minimum sheet thickness. Response surface methodology with desirability function analysis has been used to achieve maximum formability. The finite element analysis has been conducted at optimal parametric setting. Findings: The derived forming limit diagram proves that the maximum forming limit for Inconel 625 is 57.5° at the optimal parametric setting, achieved with desirability of 0.995. The outcomes of finite element analysis conducted at optimal parametric setting show excellent agreement with confirmation experiment results. Practical implications: Inconel 625 superalloy is frequently used in aircraft and other high-performance applications for its superior strength. Originality/value: It has been suggested that to enhance formability, higher tool rotation speed, minimum step-size, larger tooltip diameter and higher wall angle must be used. Wall angle is the governing parameter among all the parameters. [ABSTRACT FROM AUTHOR]

This article presents the development of a plane strain tensile test aiming at an easy classification of aluminium automotive alloys according to their formability in prototyping steps. A parametric study with finite element method is performed on three different designs inspired by literature. It is found that, due to plastic anisotropy, specimens designed for steel are not suited for aluminium alloys. One optimized specimen geometry, ensuring near plane strain state on a large zone all along the deformation range up to failure, is selected. On this geometry, tensile tests instrumented by Digital Image Correlation are performed for five different aluminium alloys (5xxx and 6xxx) in three different directions of the metal sheet (rolling, diagonal and transverse). From Digital Image Correlation analysis, necking limits are evaluated and their relevance for the ranking of alloys according to their formability is discussed in comparison with a standard formability test, namely the Limiting Dome Height test. [ABSTRACT FROM AUTHOR]

The demand for small-batch manufacturing processes has increased considerably in recent years due to the need for personalized and customized products. Single point incremental forming (SPIF) has emerged as a time-efficient approach that offers increased material formability when compared to conventional sheet metal forming techniques. However, the complexity of SPIF requires a complete understanding of the material deformation mechanism. In this study, a non-conventional contactless tool in the form of hot compressed air is employed to form a polycarbonate sheet. The influence of the contactless tool on the shaping process is modeled and analyzed with a finite element modelling (FEM). Two different models were developed and coupled to estimate the resulting shape of the sheet. A CFD model was created to obtain pressure and temperature values of the air impacting the sheet, while a transient structural model was employed to study the deformation of the sheet. The research provides a working model that is able to predict the performance of this contactless incremental forming process of polymers with high accuracy. The comprehensive FE model developed in this work is able to forecast the final part geometries and dimensions in addition to the normal strain progression. It also revealed that the primary modes of deformation in SPIF were stretching, thinning, and bending. The model was validated by experimental results, and the predicted sheet deformation was compared to the one generated experimentally, and the results obtained were in good agreement. [ABSTRACT FROM AUTHOR]