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Sand-casting is a process with a high-environmental impact in terms of both energy consumption and pollution emission. This work presents a meta-heuristic approach for the typical scheduling problem of mid-size sand casting foundries, with the objective to minimise the costs associated with labour, energy and wastes of melted material. Mid-size foundries usually have multiple parallel melting lines, each composed by a rotary and an electric furnace, and a single casting line which is the bottleneck of the process. The proposed approach has been tested on data related to a real industrial case study. Results show that, with respect to the scheduling implemented by the company, the proposed algorithm achieves a 3.2% reduction in emissions and a 4.1% reduction in energy consumption. Furthermore, these environment-friendly results are achieved while also increasing the company's profitability, by reducing total costs of more than 1% on the total revenue. [ABSTRACT FROM AUTHOR]

Additive manufacturing offers great potential for various industrial solutions; in particular, the binder jetting method enables the production of components from various materials, including sand molds for casting. This work presents the results of an extensive set of experiments aimed at enhancing the structural strengthening of 3D-printed sand molds. Structural strengthening was achieved by impregnating the sand-printed structures with two polymer materials: epoxy resin and silicone varnish. Impregnation was performed with variable parameters, such as temperature, pressure, and time. Structural strengthening using polymers was investigated by analyzing the flexural strength and impact resistance of the impregnated products and comparing these obtained values with the reference material in terms of impregnation parameters and the polymer used. Microstructural observations and an analysis of the pore filling were also performed. This approach allowed for a full assessment of the influence of processing parameters and the type of polymer used for impregnation on the properties of sand-printed structures, which allowed for identifying the most optimal method to be used to strengthen the sand molds for casting the components for electrical devices. As a direct proof of concept, it was shown that impregnation with polymeric materials could effectively strengthen the sand mold, increasing its flexural strength and impact resistance by over 20 times and 5 times, respectively. A full-scale mold was printed using binder jetting, impregnated with epoxy resin at 65 °C, and used to successfully fabricate a fully functional electrification device. [ABSTRACT FROM AUTHOR]

Nowadays, with the development of electromobility, the requirements not only for the mechanical properties but also for the thermal conductivity of castings are increasing. This paper investigates the influence of casting and heat treatment technology on the thermal diffusivity and thermal conductivity of an AlSi10MnMg alloy. The thermal diffusivity was monitored as a function of temperature in the range of 50–300 °C for the material cast by high-pressure die casting (HPDC) and also by gravity sand casting (GSC) and gravity die casting (GDC). This study also investigated the effect of the T5 heat treatment temperature (artificial ageing without prior solution treatment—HT200, HT300, and HT400) on the thermal conductivity of the material cast by different technologies. Experiments confirmed that the thermal diffusivity or thermal conductivity of the alloy depends on the casting technology. The slower the cooling rate of the casting, the higher the thermal conductivity value. For the alloy in the as-cast condition, the thermal conductivity at 50 °C is in the range of about 125 to 138 [W·m−1·K−1]. Regardless of the casting method, the thermal conductivity tends to increase with temperature (50–300 °C). Furthermore, a positive effect of heat treatment without prior solution treatment (HT200, HT300, and HT400) on the thermal conductivity was demonstrated. Regardless of the casting method of the samples, the thermal conductivity also increases with increasing heat treatment temperature. The results further showed that when artificial ageing is performed in industrial practice on castings to increase mechanical properties in the temperature range of 160–230 °C, this heat treatment has a positive effect on thermal conductivity. [ABSTRACT FROM AUTHOR]

Combining light metals like aluminum to produce lightweight structures offers a high weight‐saving and contributes to a circular economy in automotive car body construction. Compound casting is a promising process for producing car body parts. Difficulties arise in creating metallic continuity between insert and casting. Insert coatings are used to remove the oxide layer and thereby improve the wettability of the melt. This study uses a hybrid joining method to improve the metallic bond between insert and casting. Induction heating differently influences the strength properties of age‐ and nonage‐hardenable inserts. Compression shear tests characterize the metallic bond strength. Microscopic images show the influence of the process variables on the compound quality. Reproducible sound metallic bonding with low scattering is achieved by enhancing the compound casting process through induction and no insert coating. Cast wall thicknesses down to 4 mm contribute to further lightweight potential as they have the same strength level as the reference sample. A decisive factor is the insert temperature in the compound zone. Thereby, insert preheating conditions play a crucial role. Additional heat treatment of hardenable compounds leads to a further increase in metallic bond strength. [ABSTRACT FROM AUTHOR]

This review paper provides a comprehensive investigation on problems encountered in casting practices, integrating insights from diverse research areas within the field of sand casting along with the most probable and effective remedies of those problems. The study revolves around three main themes: the optimization of sand-casting processes, the selection of binders for sand-casting, and the transformative impact of artificial intelligence (AI) and advanced control systems in foundry and steel casting processes. Our paper also highlights the significance of both digital and manual optimization techniques in sand casting processes, emphasizing the transformative impact of AI technologies like Artificial Neural Networks (ANN), Fuzzy Logic, and Genetic Algorithms for enhancing efficiency, accuracy, and automation. These digital methods enable data-driven decision-making and continuous process improvement, leading to higher quality and reduced defects. Meanwhile, manual optimization, relying on the expertise and adaptability of foundry professionals, complements digital approaches by providing hands-on problem-solving and flexibility in complex scenarios. Manual optimization in sand casting involves hands-on activities that leverage the expertise and experience of foundry workers. Examples include adjusting the mold packing density to ensure uniformity, tuning the sand mixture composition for optimal mold strength and permeability, use of the binders to enhance the ratio of sand mixtures and placing sprues and risers to control metal flow and minimize defects. Together, these approaches enhance casting quality, reduce costs, promote sustainability, and maintain industry competitiveness, offering a comprehensive framework for modernizing sand casting. The main objective of this study is to offer a comprehensive understanding of how these areas converge to reshape and elevate the quality, efficiency, and sustainability of casting processes. The first section explores the optimization of sand-casting processes, that focus on critical factors such as mold types, molding sand composition, and process parameters. By identifying common grounds, including the influence of mold type on mechanical properties and the optimization of molding sand composition for reduced defects, this segment provides practical insights for achieving high-quality sand castings. The second section explores the choice of binder for sand molding, combining research from different studies that examined different natural and synthetic binders. Key findings, such as the optimization of binder content for specific casting requirements and the potential of natural binders as eco-friendly alternatives, offer guidance for practitioners seeking to enhance sand mold properties and overall casting quality. The third and final part explores the application of AI and advanced control systems in foundry and steel casting. The review highlights the transformative impact of AI techniques, including neural networks, fuzzy logic, genetic algorithms, and particle swarm optimization. These AI-driven approaches optimize customer order management, enhance supply chain efficiency, and improve green sand properties, contributing to the realization of Industry 4.0 concepts in casting processes. [ABSTRACT FROM AUTHOR]

The latest generation of high-performance cylinder blocks are produced with the Precision Sand Castings Process which sometimes uses a monolithic cast iron chill that promotes enhanced solidification conditions that improve both tensile and fatigue performance. However, monolithic chills tend to be re-used quite quickly and thus can be significantly above room temperature during the next subsequent casting. To deter the potential deleterious effects, this may cause most casting practitioners to enforce a strict room temperature condition of the chill prior to use. However, this may necessitate a higher number of chills in the system or the implementation of chill cooling stations, both of which involve higher capital investment. The authors will address the most optimal method to address thermal management of chills by documenting the mechanical and microstructural property impact and its compliance in the bulkhead (next to chill) and head bolt columns (60 mm away from the chill) to the chill temperature prior to casting. The Quality Index will reflect the chill temperature impacts based on the mechanical properties results for this manuscript. [ABSTRACT FROM AUTHOR]

In a comprehensive study, effects of casting methods such as gravity sand casting, squeeze casting and composite casting in semi-solid state and casting variables (i.e., cooling rate, stirring speed and shear forces) on the microstructure, porosity formation and mechanical properties of A356–SiC nanocomposites were investigated thoroughly. First, a step-like sample was used to make the sand casting samples to study the effects of different cooling rates that each step experienced on the properties of nanocomposite, where squeeze casting and composite casting samples were produced in a metallic mold. Once the samples were produced and prepared for the studies, grain size, shape factor, dendritic and globular microstructure, amount of eutectic phase and mechanism of porosity formation, mechanical properties and fracture surface of the samples were analyzed precisely and discussed. In addition, the effects of stirring forces, time and temperature, used in the squeeze casting and the compo-casting methods, on the morphology of the dendritic arms of aluminum matrix composites were investigated and compared with the microstructure of castings produced by conventional gravity casting. It was discovered that switching from the gravity sand casting process to the squeeze casting process delivers a less dendritic and more refined microstructure in the nanocomposite. However, composite castings produced in the semi-solid state by applying high stirring shear forces for 80 s produce the finest and the most globular and spherical microstructure. This optimized globularization condition provides desired microstructure and mechanical properties for this type of nanocomposite. The dominant failure mechanism in the composite casting samples produced in semi-solid state was ductile, where it was a mix of ductile/brittle for the squeeze casting and brittle for the sand casting samples. Finally, the effects of globularization temperature on the nucleation and growth of primary α grains were studied. [ABSTRACT FROM AUTHOR]

The unclear contraction behavior of Mg-Gd-Y-Zr alloy during low-pressure sand casting bring obstructs into the dimensional control in the fabrication of large and complex parts, restricting the further engineering applications of this alloy. This paper investigated the rule for free and constrained contraction of typical Mg-Gd-Y-Zr (Mg-9Gd-3Y-0.5Zr, VW93K) alloy during low-pressure sand casting. A series of castings with different volumes and geometric structures were designed and a 3D scanner was employed to measure different types of dimensions, which were then used for the calculation of contraction coefficients. The convergent value of free contraction coefficients was derived through statistical analysis, and the correlation between constrained contraction coefficients and geometric characteristics of castings was established by the utilizing of core volume factor. In the condition of low-pressure casting, free contraction coefficients of VW93 alloy are concentrated around a fixed value of 1.72%, constrained contraction coefficients of VW93 alloy show a decreasing linear tendency against core volume factor, and pouring pressure makes effects on free contraction. The experimental results and proposed formulas provide guidance for accurate dimensional control in fabrication of large and complex Mg-RE alloy parts by low-pressure sand casting. [ABSTRACT FROM AUTHOR]

For complex structural castings, the microstructure and mechanical properties in different parts of the castings are affected by the structure, casting process, and the temperature change during the solidification process. In this study, the microstructure, filling process, and mechanical properties of Al-5Cu-0.38Mg-0.32Mn-0.1Ag alloy cylinder heads prepared by the sand gravity casting method were systematically investigated by optical microscopy (OM), scanning electron microscopy (SEM), electronic universal testing, and MAGMASOFT5.4. The cooling curves at typical positions of the cylinder heads were measured. Although the cooling rate was different for the cylinder heads in different positions, equiaxed grains could be found. Fine equiaxed grains with a size of 62 μm were found at the cylinder head fire surface, while coarse equiaxed grains with size of 116 μm could be observed at the cylinder head intake airway side wall. The yield strength and tensile strength of the cylinder heads at different positions were 140–159 MPa, and 175–202 MPa, respectively, and their elongation percentage was 2–4%. The cylinder head fire surface has the maximum yield strength of 159 MPa. In the process of tensile fracture of the as-cast alloy, micro-cracks were first generated along the eutectic structure at the grain boundary, and then these microcracks grew, aggregated with each other, and propagated along the grain boundary, resulting in the final fracture failure of the material. [ABSTRACT FROM AUTHOR]

In the foundry industry, casting sand cores require high and low peak and residual strengths, respectively, to achieve comprehensive optimal mechanical performance. The peak and residual strengths of sand cores are positively related, highlighting the criticality of balancing them. Thus, an innovative approach comprising the incorporation of anionic surfactants into the silicate binder was introduced to balance both factors. Additionally, the investigation of the effects of the anionic surfactants on the physical properties of the silicate binder, including its colloidal stability, surface tension and adhesion, revealed that four different anionic surfactants reduced the surface tension and adhesion of the silicate binders and reduced the residual strength of the silicate-bonded sand cores. Among them, 0.10 wt% lauryl ether phosphate reduced the surface tension and adhesion of the adhesive by 49.64 and 112 mN/m, respectively, and reduced the residual strength of the sand core by 0.035 MPa. However, increasing the dosage did not further reduce the residual strength of the sand core, although it continued to reduce its peak strength. Therefore, during silicate binder modification with anionic surfactants, the dosage of the anionic surfactant must be kept at ≤0.10 wt%, as this dosage exerted the most comprehensive optimal modification effect, which was attributable to the adsorption of anionic polymers onto the surface of the silicate aggregates. This adsorption weakened the network structure of the silicate aggregates and imparted the sand cores with appropriate mechanical properties during casting. [ABSTRACT FROM AUTHOR]

The Ranganadi river basin, spanning a catchment area of 2335 km2 in the North Lakhimpur region of Assam is one of the worst flood‐affected areas in the North Eastern region of India. The basin is densely populated and the land around this river is extensively used for cultivation. Progressive migration of the banklines leads to the loss of cultivable land. Breach in embankments protecting agricultural fields during the monsoon, as well as the presence of infertile sand in agriculture fields are some of the most dominant facets of riverine hazards directly connected with the loss of livelihood in the study area The objective of this research is to assess the vulnerability of the population residing in these flood plains to the impacts of sand casting, utilizing Livelihood Vulnerability Index (LVI) approach. The research included 377 households, and a comprehensive analysis was carried out. The analysis revealed varying degrees of vulnerability for 0.306 (socio‐demographic profile), 0.489 (livelihood strategies), and 0.413 (social networks). Sensitivity values were 0.495 (health), 0.487 (food security), 0.368 (water availability), and 0.391 (psychological factors). Exposure was rated high at 0.494, indicating vulnerability to natural disasters and climate variability. These values highlighted the most vulnerable components of the population due to the disaster and helped to suggest vulnerability reduction measures. The novelty of the study based on the result is that the LVI was meticulously formulated and adapted specifically for the study area. This localized approach allowed the unique socio‐economic and environmental dynamics of the affected population to be captured very well. [ABSTRACT FROM AUTHOR]

For predicting casting deformation by FEM (finite element method) thermal stress analysis, this paper experimentally constructed and validated the Drucker–Prager (DP) model and its revised model (RDP) for the condensation zone of bentonite-bonded sand molds. The condensation zone has been known as a remarkably low-strength region in the mold, and its mechanical response should be dominant to the casting deformation. To construct the models through uniaxial and triaxial compression tests, the test pieces reproducing the condensation zone were prepared by permeating water vapor through a test piece of bentonite-bonded sand. The constructed models were then applied to the FEM stress analysis of the triaxial test to validate them by comparing the analytical stress–strain curves with the experiment. The experimental stress–strain curve after permeating water did not show any distinct yielding point; however, the analytical curve with the original DP model clearly exhibited a yielding point due to the yield criterion of the model. The distinct yielding criterion should be essentially fatal to reproduce the stress–strain relationship of the condensation zone. Contrarily, the RDP model reproduced the experimental curve with less than 10 % error and was found to be advantageous for modeling the smooth stress–strain relationship of the condensation zone. [ABSTRACT FROM AUTHOR]

The foundry industry has gradually become an important concern for carbon emissions. The composite patternless casting, which combines sand mould 3D printing and sand mould milling technologies, is an effective way to explore the potential of energy saving and emission reduction in the foundry industry. However, the technical advantages of composite patternless casting in terms of energy saving and emission reduction have not been fully studied. To address this issue, this paper combines the composite patternless casting with the modular division method, and proposes a influence modelling and analysis method for carbon emissions and carbon efficiency ratio based on the process characteristics stage. The model and method are applied to the patternless casting process of a cylinder block. And the modular division schemes of the mould were proposed. The results show that through different modular division schemes, carbon emissions can be effectively reduced by 8.39%, the carbon efficiency ratio can be increased by up to 30%. This method is helpful to describe the carbon emission influence of the patternless casting forming process, and analyse the energy saving and emission reduction potential and carbon efficiency of the process. [ABSTRACT FROM AUTHOR]

Addressing the significant issues of sand burn-on defects and interfacial reaction in sand casted 13Cr9Mo1VNb steel castings, which notably compromise the quality of the steel castings, remains a persistent challenge. The interfacial behaviors between the novel mixed sands and the steel grade were investigated under various sands. The sintering behavior of the sands was also studied without liquid steel at various holding time. In the absence of the influence of molten steel, sintering of mixed chromite-MgO does not undergo solid-solid reaction, with no detected presence of liquid phase and 2MgO·SiO 2. The mixed sands undergo sintering reactions upon contact with molten steel, yet no liquid phase is detected. This is primarily attributed to the chemical reaction between MgO and the liquid phase, resulting in the formation of forsterite, leading to the near-complete liquid phase consumption. Magnesia grains can suppress the liquid phase sintering of chromite by 13Cr9Mo1VNb, thus weakening its sintering performance. The presence of 2MgO·SiO 2 , which exhibits excellent resistance to slag (liquid phase) and steel liquid corrosion, impedes the rising of the liquid phase. Consequently, this reduces the thickness of the adhesive layer and suppresses metal penetration. The production of 2MgO·SiO 2 diminishes with the escalation of MgO addition, which increases adhesive thickness and metal penetration as the magnesia content rises. Within the scope of this study, the incorporation of 20 % MgO is suggested to mitigate burn-on defects, which may represent an advantageous selection. [ABSTRACT FROM AUTHOR]

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature 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.)

The 3D sand printing (3DSP) technology provides a richer realization path for the sustainable development of the manufacturing industry. It has the advantages of one-time molding, reducing design constraints and machining amount, and easy control of casting dimensional accuracy. Therefore, studying the impact of process parameters of the printing process on printing efficiency, resource consumption, and carbon emissions is the basis for the sustainable development of 3DSP technology. In this paper, starting from the main influencing parameters such as printing layer thickness, recoater speed, printing angle, and single printing quantity, a relationship model between printing parameters and carbon emission sources is constructed. A total factor carbon emission prediction model of 3DSP process including the impact of capital and labor is established. Build an influence relationship with printing parameters as independent variables and carbon emissions as dependent variables. Taking the sand casting industry as an example to verify the above model, the experimental results show that the thickness of the printing layer has the greatest impact on carbon emissions. When the layer thickness is 0.36 mm, the speed of the recoater is 0.22 m/s, the printing angle is (0°, 0°, 90°), and the single print quantity is 84, the total carbon emission is the lowest and 28.77% less compared to the parameter with the highest carbon emission. The average relative error of the predictive model is 1.929%. The results of this study can provide some new ideas for sustainable development of additive manufacturing technology. [ABSTRACT FROM AUTHOR]

The International Journal of Metalcasting highlights research projects funded by the American Foundry Society (AFS) that aim to support the metalcasting industry in North America. These projects cover a range of topics, including new technology, improved processes, and knowledge transfer. Specific projects include developing digital tools for accessing metalcasting best practices, investigating new materials and processes for investment casting, and studying the effects of different materials on the mechanical properties of cast iron. The AFS also collaborates with other organizations on projects related to additive manufacturing and improving casting quality. In addition to funding research, the AFS offers various resources and services for individuals in the metalcasting industry. Their website provides tools for selecting casting processes and alloy properties, as well as a directory of metalcasters. AFS also offers a social network called Casting Connection and an online library with access to technical articles and reports. They host conferences, workshops, and webinars on topics related to metalcasting, and they have a mobile app for accessing their library resources. [Extracted from the article]

Permanent mold (PM) and semi-solid (rheo) casting in ductile iron castings (DIC) were studied, and the microstructure was aimed to be chill free in as-cast condition. Denitrification was conducted understanding solubility properties of nitrogen in base molten iron, and re-nitrification was strictly avoided during molten treatment by Mg alloy. As the results, chill-free knuckle castings were possible with both casting methods in as-cast condition. The knuckle castings had no shrinkage cavity also. The solidification time by rheocasting was shorter than that of PM casting. It was approximately one in two and a half. The castings had ultrafine spheroidal graphite which were mostly under 10 µm. The graphite structure by rheocasing method was finer and more uniform than those of PM casting. The tensile strength in castings with both casting methods was approximately 1.3 times keeping elongation over 10% comparing with conventional sand knuckle castings. It was concluded that free nitrogen (NF) promoted chill formation, and chill could be avoided by promoting denitrification and minimum re-nitrification. [ABSTRACT FROM AUTHOR]

In recent development of casting traceability, it has been noticed that many casting manufacturing processes that involve the use of sand cores often lack proper traceability back to the cores used in their production and the supporting production information. Most marking symbols applied to sand cores using existing marking methods not only exhibit unstable code readability but also pose critical risks to the surface quality of sand cores. In response, we developed and tested a digital-twin core rack aimed at transferring digital codes to sand cores without contact with their surfaces. By utilizing infrared sensors for real-time object detection, the core rack can transfer digital identical codes from the core-making machine to the core rack, and subsequently to the casting machine. This digital code encompasses all relevant process data of a sand core, from core making to de-coring. Moreover, the various sensors embedded in the core rack were designed to monitor air humidity, temperature, and vibration events during the transport and storage of the cores. These parameters are especially critical for maintaining the quality of inorganic sand cores. The study demonstrates the successful application of each component within this conceptual framework. Looking ahead, it is imperative to update the hardware of this concept to ensure its adaptation to the demanding conditions of an industrial environment. [ABSTRACT FROM AUTHOR]

An evaluation method for the initial penetration of molten cast iron into the sand mold was suggested based on the laboratory-scale penetration experiments for the cast iron. The horizontal penetration depth of the molten cast iron into the sand core was analyzed using the capillary model. The early stage of the penetration was discussed, and it was clarified that the penetration is not stopped by the solidification but is stopped by the decreasing of the equivalent pore radius. It was explained that the equivalent pore radius decreases with increasing the penetration depth, and the penetration is stopped when the critical pressure, i.e., the pressure required for the penetration, becomes higher than the pressure which is acting on the penetration front. Based on the analysis, an evaluation method of the penetration of depth at the early stage of the penetration was suggested. The analysis method was applied for the other type of metals (mercury and steel) as well, and reasonable results were obtained. A simplified finite-element model of liquid iron penetration into a sand core was developed, accounting for heat exchange between the melt and the porous medium, at different pore geometries. [ABSTRACT FROM AUTHOR]

The important supporting component in a gas turbine is the casing, which has the characteristics of large size, complex structure, and thin wall. In the context of existing 3DP sand casting processes, casting crack defects are prone to occur. This leads to an increase in the scrap rate of casings, causing significant resource wastage. Additionally, the presence of cracks poses a significant safety hazard after the casings are put into service. The generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand mold. Therefore, the types and causes of cracks in stainless steel casing products, based on their structural characteristics, were systematically analyzed. Various sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature concession. The optimal sand mold structure was used to cast casings, and the crack suppression effect was verified by analyzing its eddy current testing results. The experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the casing. This research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs. [ABSTRACT FROM AUTHOR]

Copyright of Foundry Technology (1000-8365) is the property of Foundry Technology Editorial Office 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.)

Sand casting is a crucial manufacturing step in creating a quality product that will meet the demands of the market. Four common metals aluminum, brass, gunmetal, and cast iron are evaluated to determine which makes the best riser. In this study, we use Taguchi L9 orthogonal array design of experiment (DOE) analysis to the melting and vent hole characteristics of sand and develop a mathematical model using Taguchi methods. It is necessary to concentrate the size and geometry of the riser. The riser design is optimized by process parameters of major diameter, minor height, and diameter of the riser. By balancing many factors, including riser design, melting, sand, and vent holes, we found the optimal configuration. The end objective is to improve the material's mechanical properties. As a result of its superior dimensional geometry, simplicity of pattern development, higher production rate, and decreased solidification time compared to another casting, investment casting has become increasingly popular. It is common to practice casting both ferrous and non-ferrous materials in the sand since doing so yields a high-quality, low-cost item. Most of the small-scale industries are making the cast material by sand casting process that observed the yield of casting ranges from 50 to 55% only. 50%on the raw material is spent for the riser, runner, and gating system. Out of 50%, the riser alone has 25% of the raw material. It is clear that, the riser having more volume of raw material. [ABSTRACT FROM AUTHOR]

The object of research is the technology of manufacturing «Body»-type shaped castings of the from medium carbon steel in one-time sand molds. The existing problem is that the design of the casting and foundry equipment significantly affect the formation of internal defects in castings. This especially applies to steel castings, the technology of which is more complicated than the technology of cast iron castings due to much worse casting properties of steel. To determine the influence of the location of surpluses on the «Body»-type steel castings of the on the formation of shrinkage shells, computer modeling was used, in the process of which 5 computer experiments were conducted with different sizes and geometries of surpluses. According to the simulation results, it was found that with some technological options, there is a risk of the shrinkage shell penetrating into the casting body. The use of a cylindrical surplus of a rectangular cross-section with fillets ensures complete absorption of the shrink shell in the place of surplus installation. Using an excess round section at the installation location does not guarantee absorption of the shrink shell. The determining factor affecting the coefficient of increase in the depth of the shrinking shell is the excess volume. This influence can be described by a functional dependence of the logarithmic type with the coefficient of determination R2 = 0.82. It was determined that the ratio of the diameter of the inlet to its height does not affect the coefficient of increase in the depth of the shrinking shell. The resulting functional dependence allows to set the excess volume that provides a minimum growth factor while simultaneously preventing excess metal consumption. The presented study will be useful for machine-building enterprises that have foundries in their structure, where shaped castings are made in one-time sand molds. [ABSTRACT FROM AUTHOR]

Gravity sand casting simulations require accurate modelling of heat transfer phenomena to reliably evaluate the expected quality of the produced parts. Average model parameters can be easily retrieved from a validated database. However, these parameters are highly dependent on the specific sand used and the actual forming process in the foundry. Furthermore, the heat transfer from the solidifying alloy to the mould surfaces is not precisely known, so simulation models usually use typical values for overall heat transfer coefficients. Most research works investigate individual parameters, whereas heat transfer phenomena largely arise from their interaction together. Therefore, the present work describes a combined experimental and computational method based on genetic algorithm techniques for determining the most important parameters for heat transfer in a sand mould. The experiments examine both virgin and reused sand, as these are alternatively used in the foundry for mould forming. The density, thermal conductivity, and specific heat capacity of the different sands are identified, along with heat transfer coefficients. The counterproof simulations demonstrate that the standard parameters are quite reliable for virgin sand. However, in the case of reused sand, the identified parameters lead to more reliable results. [ABSTRACT FROM AUTHOR]

Scandium (Sc) is attracting attention in aerospace and special-vehicle industries due to its potential benefits, but research on the effect of Sc addition on the phase formation and mechanical properties of Al-Cu casting alloys (i.e., 2xx.x series) have been conflicting. To explore the potential of Sc in the Al casting industry, Al-Cu-based A206 alloys with different Sc contents were used to cast cylinder heads of special vehicles in an industrial sand casting environment. The results showed that Sc addition promoted the formation of W-AlCuSc rods precipitates within α-Al grains and the large W-AlCuSc intermetallic particles at α-Al grain boundary by redistributing Cu atoms from the α-Al grain interior to the boundary. The formation of the W-AlCuSc phase and the redistribution of Cu atoms reduced the yield strength of both as-cast and T6-state A206 alloys. Solidification calculations indicate that W-AlCuSc phase evolves from primary Al3Sc phase or from supersaturated α-Al phase. It has also been experimentally verified that the formation of the W-AlCuSc phase is dependent on the cooling rate and can be suppressed by increasing the cooling rate. These findings provide a reference for the efficient utilization of Sc in casting industries. [ABSTRACT FROM AUTHOR]

Preparing uniform soil samples is essential for obtaining reliable results in the physical modeling of geotechnical structures, such as retaining walls and piles. The air pluviation method is a common approach adopted by researchers and engineers to reconstitute large-scale sand beds with high degrees of homogeneity and uniformity. This paper investigates the uniformity of sand beds prepared using the conventional manual sand pouring method, its potential impact on test results, and how creating a more uniform sand bed can enhance the reliability of the results. To achieve this goal, a novel portable sand pluviator capable of reconstituting sand beds inside a frustum confining vessel (FCV) apparatus at a high level of uniformity is adopted. The pluviator is utilised to prepare sand beds inside the FCV, and the uniformity of the resulting sand bed is assessed and compared with those prepared using the manual pouring method. Next, in order to investigate the influence of uniformity of sand beds on the outcomes of a large-scale test, a large-scale experiment involving the determination of the bearing capacity of a open-ended single-helix helical pile within the FCV is considered. Numerical analysis investigates how sand bed uniformity affects bearing capacity without extensive testing. It uses data from initial research and employs Latin Hypercube Sampling to determine the required simulations for accurate measurement of the impact of sand bed uniformity on bearing capacity. The results of this set of numerical simulations are then thoroughly analysed to assess the impact of the sand pouring method on the reliability of the experimental outcomes. Analysis of the results show that preparation of uniform sand beds at the desired relative density is one of the key elements in obtaining accurate and reliable experimental results in geotechnical physical modelling problems. [ABSTRACT FROM AUTHOR]

• Gd addition to the Mg-4Al-5RE alloys produced by various casting methods can refine the grains and modify the morphology of the acicular Al11RE3 phase to the short rod-like. • Gd addition increases the impact toughness due to the lower tendency of the modified second phases toward crack initiation. • The fine-grained HPDC alloys have an inconsistent strain rate sensitivity during the impact event. • The fine-grained HPDC alloys have excellent impact toughness but show an insufficient plastic deformation capacity. This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd (RE represents La-Ce mischmetal; x = 0, 0.2, 0.7 wt.%) alloys cast by high-pressure die casting (HPDC), permanent mold casting (PMC), and sand casting (SC) techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al 11 RE 3 phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content, the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {10 1 ¯ 2} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity. [ABSTRACT FROM AUTHOR]

The pouring of sand casting is accompanied by severe heat conduction, and there is an urgent need to investigate the pyrolysis properties of foundry sand. The main purpose of this study was to investigate the pyrolysis behaviors of resin sand, including precoated sand (PCS), hot box sand (HBS), and warm box sand (WBS), at heating rates of 20 °C/min, 30 °C/min, and 40 °C/min in nitrogen and air atmospheres. The mass loss of the resin sand was monitored continuously with a simultaneous thermal analyzer, and the kinetic parameters of the resin sand were calculated based on the Coats–Redfern method and thermal data. The average mass loss of the resin sand during pyrolysis was 3.03%, which was much smaller than that of the other sands. The volatile release characteristic index of resin sand could not be calculated based on this concept. To solve this issue, the term Tstv/mloss was established, and its value was determined. With increasing heating rates from 20 °C/min to 30 °C/min and from 30 °C/min to 40 °C/min, the mass losses of the resin sand increased by 0.79% and 0.64%, respectively, and the volatile release characteristic indices of the resin sand increased by 3.8 × 10−10 and 1.06 × 10−9, respectively. In addition, the mass losses and volatile release characteristic indices of resin sand in an air atmosphere were greater than those in a nitrogen atmosphere. With increasing heating rate, the activation energy of the resin sand decreased in a nitrogen atmosphere. The findings concerning the thermal decomposition behaviors of resin sand provided a theoretical basis for the pouring step of the sand casting process. [ABSTRACT FROM AUTHOR]

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The International Journal of Metalcasting provides information on the funding and involvement of the American Foundry Society (AFS) in metalcasting research projects. AFS collaborates with government funding, industry contributions, and other means to support research in the metalcasting industry. They are currently involved in partnerships such as the American Metalcasting Consortium (AMC) funded by the Defense Logistics Agency (DLA). AFS also funds research projects on various topics including virtual knowledge transfer platforms, cost-effective fast response and sustainability for critical castings, and refining austenite in gray irons. The text also mentions resources like the AFS Casting Alloy Data Search and the Peters-Robison AFS Metalcasting Library, as well as upcoming conferences and workshops organized by AFS. [Extracted from the article]

The influence of external magnetic field in the sand casting process on the microstructures and mechanical properties of A357 aluminum-silicon (Al–Si) alloys was investigated. Different magnetic field intensities such as 0, 6.3, and 10.7 mT were applied respectively by Helmholtz coils with an autotransformer. Applied an external magnetic fields during the solidification process, the microstructures of as-cast A357 alloy performed grain refinement of α-Al, reduction of secondary dendritic arm spacing, and fibrous structure of eutectic silicon. After T6 heat treatment, the morphology of eutectic silicon particles became fragmented and spheroidized. Therefore, the magnetic field enhanced the mechanical properties of A357 alloys, including hardness, ultimate tensile strength (UTS), yield strength (YS), and elongation (El). Compared the samples without magnetic field and with the field of 10.7 mT, the values of hardness, UTS, YS and El increased 17.9%, 10.6%, 8.8%, and 48%, respectively. The higher the magnetic field we apply, the better performance of sand-cast A357 we can get. Moreover, the magnetic field during A357 solidification process attributed to the preferred orientation (111) of α-Al and uniformly dimples in fractography. In conclusion, an inexpensive and facile technique has been proposed to enhance the quality index of the sand-casting A357 alloys via the influence by external magnetic fields on the microscopic properties of materials, especially for α-Al grain refinement and eutectic-silicon spheroidization. [ABSTRACT FROM AUTHOR]

The process of ablation casting (AC) is a novel sand casting technique that not only offers the benefits of conventional sand casting (CSC), but also offers opportunities to overcome some of its shortcomings. In this research, A413 and A356 alloys were cast via CSC and AC processes. The CSC simulation process showed that the solid fraction parameter at different times indicated A413 to be more suitable than A356 for the AC process. The experimental results showed that AC process increased the cooling rate of both alloys (4–6% times for A413 and 9–10 times for A356), compared to CSC. Moreover, prolonging water spray delay time led to decrease in the cooling rate. Indeed, the AC has a more significant impact on reducing SDAS in A413 (60–75%) compared to A356 (45–61%). Moreover, decreasing the Si content in hypo-eutectic Al–Si binary systems limits the water spray delay time at a similar superheat. Besides, the reduction of eutectic silicon aspect ratio is nearly equal in both A413 (77–81%) and A356 (80–83%) alloys, through the AC compared to CSC. Furthermore, through the use of AC, the UTS of A413 and A356 increased by 112–130% and 78–100%, the YS of A413 and A356 increased by 8–21% and 31–42%, and the elongation of A413 and A356 increased by 333–620% and 110–252%, respectively, compared to CSC. These experimental results confirmed the simulation results. Finally, the transition of fracture from cleavage plane to dimple form occurred through AC for both A413 and A356 alloys, compared to CSC. In sound casting, it was found that the role of eutectic silicon in fracture was more prominent than Fe-containing intermetallic compounds. [ABSTRACT FROM AUTHOR]

This paper proposes a methodological framework to develop a data-driven process control using pure industrial production data from a cast iron foundry, despite the limitation of complete casting traceability. The aim is to help sand foundries to produce good castings. A reference foundry, which produces mainly automotive and oven parts with automatic sand molding and pouring machines, was selected. Past data, where only good castings were produced, were extracted from the database to determine parameter control limits (upper and lower control limits) with the aid of statistical approach. To identify critical process parameters associated with casting defects, process data from the zero and high scrap production batches were systematically compared. This method clearly identified unstable parameters without exact synchronization between inline and part quality data. Molding sand moisture, temperature and compactability, liquidus temperature of the melt, phosphorus content, carbon equivalent and pouring temperature were found to be the critical parameters to be stabilized. Finally, a regression model for predicting and controlling of molding sand moisture and liquidus temperature of the melt was created. The determined boundaries and the models were helpful for the foundry in assisting ongoing production control and correction of process inputs to achieve target casting quality. [ABSTRACT FROM AUTHOR]

The paper presents the results of the analysis of cooling curves of cast iron with approximately eutectic composition rasterized at different rates of cooling and ingot crystallization. The test samples were in the form of rods with a diameter of 30,0.mm and a coagulation modulus M = 0.75 cm. They were cast in a sand mould made of furan mass placed on a chill in the form of a cast-iron plate, with which one of the front surfaces of the rod casting was in contact. In this way, a differentiated cooling rate along the rod was achieved. At selected distances from the chiller (5, 15, 25, 25 and 45 mm) thermocouple moulds were placed in the cavity to record the cooling curves used in thermal (AT) and derivation (ATD) analysis. The solidification time of the ingot in the part farthest from the chiller was about 200s, which corresponds to the solidification time in the test cup AT. An analysis of the recorded cooling curves was performed in order to determine the values of characteristic points on the AT curve (Tsol. Tliq, ΔTrecal., τclot, etc.). Relationships between cooling time and rate and characteristic points on AT and ATD curves were developed. For example, Tsol min changes in the range of 1115 - 1145 for the range of cast iron solidification times in the selected ingot zone from ~ 70 to ~ 200 s, which corresponds to the process speed from 0.0047 to 0.014 [1/s]. The work also includes an analysis of other characteristic points on the AT and ATD curves as functions of the solidification rate of cast iron of the same composition. [ABSTRACT FROM AUTHOR]

The automotive industry is undergoing a rapid evolution to meet today's challenges; therefore, continuous innovation and product development are needed. Validation tests on prototypes play a crucial role in moving new components into industrial production. There is also a pressing need for faster prototyping processes. In this context, rapid sand casting (RSC), based on additive manufacturing technology, offers a promising solution for a quick production of sand molds. While this technology is already employed in the industry, the need to deepen the general understanding of its impact on the casting properties is still a relevant item. In this study, different geometries of automotive prototypes made of aluminum EN AC 42100-T6 alloy were experimentally analyzed. Microstructural examinations, tensile tests, and fractography and porosity analyses were conducted. The findings demonstrate the considerable potential of RSC, giving, in general, high mechanical properties. A comparative analysis with prototypes produced through traditional sand casting revealed similar results, with RSC exhibiting superior yield strength and stress at brake. However, both technologies revealed a reduced elongation percentage, as expected. Future efforts will focus on standardizing the RSC process to enhance ductility levels. [ABSTRACT FROM AUTHOR]

This paper investigates the casting defects of a stainless steel pump impeller manufactured through the sand casting process. The material characterization of austenitic steel AISI 316L was initially carried out, which examined the chemical composition of the casting and its microstructure. The next step was to determine the cause of the casting defects using numerical simulations. The numerical simulations were performed using ProCAST software (Version 18.0). Initial results of the filling and solidification simulations were conducted using the parameters employed in the actual casting process, revealing casting defects in corresponding locations. The casting process was subsequently modified to achieve improved results. This involved reconstructing the gating system, redesigning the riser, and incorporating a cylindrical chiller. The results show that the modified casting process significantly reduces the occurrence of defects in the final product. The study provides useful insights into the analysis and modification of the casting process for stainless steel pump impellers produced through sand casting. The results can help improve the quality of such products and reduce production costs associated with casting defects. [ABSTRACT FROM AUTHOR]

The object of research in the paper is the production technology of casting «brake drum» from cast iron of the basic grade SCh20 according to GOST 1412-85 (DSTU EN 1561, EN-GJL-200). The existing problem is that due to the imperfection of the technological processes of manufacturing castings, final internal defects of a shrinking nature are possible. This can lead to a decrease in the strength and operational reliability of the drums, regardless of the chemical composition, which may meet the technical conditions and should provide the specified strength indicators according to the grade of cast iron. Based on the results of 3D modeling, it has been found that with the existing technology of manufacturing brake drum castings in one-time sand molds, final shrinkage defects are formed in the upper part of the casting. To eliminate this problem, a decision is proposed to increase the allowance for mechanical processing on the upper surface of the casting. The possible excess of the mass of the casting and excess consumption of the alloy that will occur when implementing this solution can be compensated by reducing the allowance on other surfaces based on their optimization by the method of dimensional chains and reducing the thickness of the casting wall. For this, a reduction in the carbon content in the alloy is proposed as a factor in increasing the tensile strength of cast iron. On the basis of 90 serial meltings in industrial conditions, the possibility of increasing the strength limit of cast iron by approximately 11 % by reducing the average carbon content in cast iron from 3.45 % to 3.4 % has been proven. The proposed solutions are the essence of improving the production technology of cast brake drums, which are produced by casting in one-time sand molds. The presented study will be useful for machine-building enterprises that have foundries in their structure, where iron is melted for the production of castings. [ABSTRACT FROM AUTHOR]

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality, resulting in a high scrap rate. A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency, which includes the random forest (RF) classification model, the feature importance analysis, and the process parameters optimization with Monte Carlo simulation. The collected data includes four types of defects and corresponding process parameters were used to construct the RF model. Classification results show a recall rate above 90% for all categories. The Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF model. Finally, the classification model was applied to different production conditions for quality prediction. In the case of process parameters optimization for gas porosity defects, this model serves as an experimental process in the Monte Carlo method to estimate a better temperature distribution. The prediction model, when applied to the factory, greatly improved the efficiency of defect detection. Results show that the scrap rate decreased from 10.16% to 6.68%. [ABSTRACT FROM AUTHOR]

The production of high-quality castings without foundry defects at minimal production costs is a constant priority for foundries. Innovation and optimization of production processes are key to achieving this goal. Computer simulation of foundry processes offers a modern alternative to expensive and time-consuming experiments in real foundries and provides a reliable representation and analysis of casting and solidification processes. A detailed analysis of the casting and solidification simulation results allows the prediction of various risks that can cause defects in cast castings, thereby reducing their quality and, last but not least, the cost of their production. This paper deals with the analysis of a computer simulation of the casting of a brake disc in a Slovak foundry. This brake disc has had shrinkages and micro shrinkages that reduce the internal quality of the casting. These defects occurred in the ribs in the upper part of the casting under the feeders. A computer simulation of the casting and solidification of this casting was made according to the real conditions. It turned out that the designed gating system with a system of feeders was not sufficient to eliminate the emerging defects. A new layout for the feeders was proposed, which ultimately eliminated the occurrence of defects based on the results of the computer simulation. The input parameters were set to be as close as possible to the actual needs of the foundry. Moreover, 3D models of the assemblies were designed in SolidWorks Premium 2015 x64 Edition CAD software, and the filling and solidification simulations were performed using the NovaFlow & Solid CV 4.6r42 simulation program. [ABSTRACT FROM AUTHOR]