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Nowadays Unmanned Aircraft Vehicle (UAV) technology has been developed rapidly, including in Indonesia. LAPAN Surveillance UAV (LSU)-02 is one of the fixed-wing UAVs in Indonesia. It has been developed by LAPAN, the national aerospace research agency of Indonesia, for mapping and surveillance. The UAV has been equipped with automatic flight control system. However, the automatic system was not made based on the flight dynamic characteristic of the UAV. Therefore, optimization in certain flight condition becomes difficult. Hence, the aim of this research is to develop a mathematical model of LSU-02 for automatic control and guidance system design. A 6-DOF (degree of freedom) non-linear mathematical model was build based on aerodynamics, weight and balance, and propulsion of the UAV. The model is then evaluated by performing numerical simulation on the designed cruise condition. The simulation results show a dynamically stable characteristics for longitudinal motion and an unstable characteristic for lateral-directional motion.

The contemporary World is focusing on the least exploitation of natural resources as the regeneration of nature is being experienced costly. The automotive and aerospace field has similar motive where the least consumption of fuel is targeted through achieving maximum possible fuel efficiency. Curtailment of the structural weight of automobiles and aircrafts can contribute significantly to accomplish efficient fuel consumption. However, lightweight design and production of these structures are challenging as low weight is possible through multi-materials structures for which competing joining medium is needed. Friction based joining processes are preferable and the current paper overviews typical joining techniques to apply in automotive and aerospace industries.

The interest for polymer based nanocomposite materials has increased exponentially in the recent years, the success being ensured by the special properties and the wide range of applications across multiple high-end industrial areas. This paper presents the main components needed for the synthesis of nanocomposite materials with particular characteristics and analyzes the development perspectives in order to extend the applications in the aerospace sector.Research has shown that there are great challenges and opportunities in the development of nanocomposites, with special efforts to improve their multifunctional features by identifying and selecting the main components.To select the constituent phases, the properties (chemical, mechanical, thermal, electrical, etc.), the accessibility of the polymer matrices and the particle characteristics (shape, agglomeration tendency, size distribution, specific surface, etc.), compatibility / synergy between components are key factors for nanocomposite materials structure and properties. For the formation of composites with applicability in the aerospace domain a nanoparticle type system (minor component of type M2Oxundoped / doped, SiC, graphene oxide etc.) and an organic one (major component - PMMA, PVA, PS, PI, epoxy resins, phenolic resins etc.) are currently used and with various types of additions, ensure synergy and compatibility between components. Current technological requirements have stimulated the development of nanocomposites with optimal properties for targeted applications.

Due to their high strength and stiffness at comparatively low weight, lightweight construction materials such as fiber reinforced plastics (FRP) are used in a variety of technical systems. The areas of application range from aerospace and renewable energies to the automotive sector, which is gaining increasing importance. The non-destructive testing (NDT) by means of air-coupled ultrasound is a decisive factor for the detection of production and operation induced defects. As a result, it is possible to examine components regarding possible defects without contact or coupling medium. By using carbon fiber reinforced plastic (CFRP) pipes with different geometries, it was possible to demonstrate the suitability of air-coupled ultrasound for defect detection. For this purpose, guided waves were contactlessly excited in the pipe, which circumferentially propagated along the components’ cross-section. Based on the amplitude and phase characteristics of the waves, defects could be detected in different axial and circumferential positions within short inspection times of a few seconds. The developed testing method is automatable and hence offers a high potential for future quality control in serial production.

Carbon epoxy composite T300/914 which has wide applications in aerospace industries, as a structural material, has been analyzed, to determine the interlaminar fracture toughness. Laminates with a thickness of 4.6 mm, consisting of 48 layers of T300/914, are considered for estimating the inter-laminar fracture toughness. These specimens have been fabricated by hand layup method followed by controlled curing in an autoclave. Tests have been conducted in accordance with ASTM standards, for Mode I by Double Cantilever Beam (DCB) test and End Notch Flexure (ENF) test for Mode II. Pulse-Echo test results and C-Scan images of the specimens were also analyzed to locate the exact position of delamination. During the preliminary tests, it was found that the interlaminar fracture toughness varied, because of bonding of release film with the sides of the laminate. By Modified Beam Theory, Mode I and Mode II fracture toughness values of the prepared specimens were found to be 0.090 kJ/m2and 0.542 kJ/m2, respectively. It was also noted that the fracture toughness of the specimens from the same laminate varied with the degree of compaction.

3D printing with the use of powdered metals is more and more commonly used, and its technologies as SLM, SLS or LMD, have developed strongly in the last few years. AM technologies allow to the production of complicated elements that are difficult to produce in another process. Additive manufacturing is increasingly used in the automotive, aerospace and biomedical industries. The most commonly used material in these areas is titanium. Titanium alloy Ti6Al4V is superlative for a machine elements requiring high strength. It is characterized by high mechanical properties, low density, high corrosion resistance and biocompatibility with human tissue. For this reason, this material is excellent for the production of biomedical implants The aim of the paper is to compare the properties of titanium alloy Ti6Al4V under static loading conditions for samples made by 3D printing and metallurgical method. On the basis of literature analysis, the results of experimental tests of samples made by use of additive manufacturing method in SLM technology were presented.

Thin sheet components are increasingly used in several advanced industries, such as aerospace and automotive. In these sectors, improved mechanical and surface properties are highly demanded meeting, in several cases, also weight and aesthetical requirements. The industrial routes typically involved in the manufacturing of this kind of components are based on the combination of joining, forming and cutting technologies, whereas efficient production strategies are planned adopting modelling and simulations based on an integrated approach. The present work deals with the development of an integrated numerical model able to simulate the manufacturing route for formed thin sheets, rolled, welded by friction stir welding (FSW) technology and finally shaped by means of a single point incremental forming (SPIF) process. In concept, the approach is based on the link between two submodels simulating the two consecutive processes. The first submodel, taking as input the geometry and the mechanical properties of the anisotropic rolled aluminum foil, simulates in the ABAQUS environment, the FSW process. Tool geometry and path, rotational velocity, advancing speed, and other material parameters are defined as input values, providing, as output, the mechanical properties of the welded sheet, the affected zones, and the residual stress-strain fields. This output feeds the SPIF sub-model that evaluates the deformation of the sheet according to a defined process planning, allowing for the simulation of the entire manufacturing chain.

More than ten years of Research and Development focused on phased-array inspection of aerospace Polymer Matrix Composites (PMCs) is presented. This work includes basic research designed to understand the propagation of ultrasound through composite materials, as well as optimization of phased-array probes and inspection strategies for composite parts. Successful implementations of these strategies for fully automated on-line inspections are presented including a discussion of how challenges were overcome and the promise of new acquisition and analysis tools. Composite materials present unique challenges for ultrasonic inspection including complex shapes and a wide range of potential flaws and defects. For automated inspections, part-to-part variability and the need to inspect at production rates pose additional challenges. The methodologies presented are based upon laboratory experiments performed in conjunction with modeling and simulations, which are used to optimize inspection strategies. A significant challenge that should not be under estimated is creating industrial-quality test specimens with realistic defects of known size and location that can be independently verified. In projects with industry and the Air Force Research Laboratory (AFRL), work has focused specifically on using surface-adaptive techniques to inspect parts with complex shapes including small convex and concave radii that are typically found on stringers, blades and wing structures. Experimental and simulation results have been evaluated for flat and curved linear arrays as well as matrix arrays, which are used with and without surface-adaptive techniques for purposes of comparison. Fully automated on-line inspections that have been operating for several years as well as recent large-scale implementations demonstrate the ability to inspect a wide range of different composite parts at production rates. Rapidly increasing computer processing power together with ultra-high data-transfer rates will continue to enable computationally intensive signal and image processing in near real time. These advancements hold promise for greater use of automated inspection and the ability to incorporate sophisticated data acquisition and analysis tools into portable systems that can then be used in the field, for example, in depots and onboard ships.

The advent of Automated Fiber Placement (AFP) systems have aided the rapid manufacturing of composite aerospace structures. One of the challenges that AFP systems bring is the variability of the deposited prepreg tape layers, which are prone to gaps, overlaps and twists. The current detection method used in industry involves halting fabrication and performing a time consuming visual inspection of each tape layer. Typical AFP systems use a quartz lamp to heat the base layer to make the surface tacky as it deposits another tape layer. The innovation discussed in this paper is to use the preheated base layer as a through transmission heat source and inspect the newly added tape layer in situ using a thermographic camera mounted onto the AFP structure. Such a system would not only increase manufacturing throughput by reducing inspection times, but would also aid in process development for new structural designs or material systems. To this end, a small thermal camera was mounted onto an AFP robotic research platform at NASA, and thermal data was collected during typical and experimental layup operations. The data was post processed to reveal defects such as tow overlap/gap, wrinkling, and peel-up. Defects that would have been impossible to detect visually were also revealed in the data, such as poor/loss of adhesion between plies and the effects of vacuum debulking. This paper will cover the results of our experiments, and the recent progress on the data reduction algorithms in preparation for machine learning development.

Electrically coupled processes have proved themselves very effective in the search for optimizing manufacturing processes of metallic components in various industries ranging from automotive or aerospace down to medical applications. The present work reviews the fundamental blocks introduced into the finite elements simulation software FORGE® to deal with electrically assisted forming processes such as electric upsetting and joining, spot welding and capacitor discharge welding. This work has been carried out using intrinsic coupling between the physical blocks defining the charge conservation equation, the energy conservation, the linear momentum equilibrium, sophisticated metallurgical databases, high-performance parallel computing and advanced remeshing algorithms to cover large deformations. We also present experimental and numerical studies that have been carried out to validate the present model for its two main applications in electric upsetting and resistance welding.

This work describes the comparison of laboratory guided wave (GW) structural health monitoring (SHM) data and simulated GW data for an aluminum fuselage section undergoing testing at the FAA. The test set up consists of 12 piezoelectric wafer transducers which are each actuated individually. Data is then collected from each non-actuated sensor. The structure tested was an aluminum fuselage panel and the structure simulated was two bays of that panel. The simulations were completed using a custom code implementing the elastodynamic finite integration technique to model GW SHM of metals. The goal of the simulation is not only to provide a deeper understanding of real-world phenomena, but also to enable a cost-effective and feasible route to studying a large number of defect detection scenarios. Modeling the physics of GW SHM systems provides a path for understanding system dependencies, capabilities and limitations for different damage detection scenarios. This work describes the method for simulating the GW data and the method for collecting GW data in the laboratory setting. We also describe initial results comparing the data sets (experimental and simulation) for a single defect scenario and the resulting conclusions about the use of simulations for GW SHM system validation.

Graphene has inspired the world since its discovery in 2004. There have been thousands of papers, patents of graphene-based nanomaterial and it has been exploited in variety of applications. Graphene is two-dimensional (2D) nanomaterial with extended network of benzene rings, it is stronger than stainless steel and has high conductivity. The thermal transport of graphene is flourishing area of research, especially for the use in thermal management applications. Graphene oxide is the functionalized form of graphene with most of the graphene features intact. In this research we synthesized the Graphene oxide using improved Hummer’s method and furthermore it was characterized by various analytical techniques. Here we described the synthesis of graphene oxide, characterization and have highlighted its possible application in aerospace technology.

Recent developments in metal additive manufacturing (AM) has created a lot of interest in sectors including automotive, aerospace and biomedical engineering. It is imperative that the components manufactured additively be inspected for flaws, mechanical properties and dimensional accuracy. Several non-destructive testing (NDT) techniques such as X-ray computed tomography and conventional ultrasonic testing have been implemented to evaluate the quality of these components. Recently, research has been focused on techniques that can perform non-contact testing and carry out an online inspection layer by layer while the component is being fabricated. Laser based ultrasonic technique has been found to be a promising method owing to its non-contact nature and ability to operate in harsh environments. In our study, narrow band lamb waves were generated using a pulsed Nd-YAG laser system consisting of a spatial array illumination source. The generated wave modes were detected using a two-wave mixing based laser interferometer. The wavelength-matched method enabled generation of specific lamb wave modes for in-situ inspection of additively manufactured components.

The production of Ti–6Al–4V components is of great importance for many fields, especially the aerospace industry. High-performance parts made of Ti–6Al–4V are traditionally produced by hot forging and require expensive dies. Besides, to obtain net shape parts, extensive machining operations are used which may entail a material yield of less than 10 %. For many applications, net-shape technologies such as additive manufacturing (AM) could enable a more resource-efficient production. However, manufacturing costs and process time in additive manufacturing rapidly rise with part size. Thus, the disadvantages of AM and forging operations could be levered by mating both processes to new process chains, allowing to reduce the number of processing steps and to avoid high material waste. Innovative process chains combining these two manufacturing techniques have been put forward recently, but almost no scientific knowledge on such processing route exists. The present study focusses on the design of a novel processing route and presents an investigation of the hot deformation behavior and microstructure evolution of Ti–6Al–4V material, which was produced by means of wire-arc additive manufacturing (WAAM). The microstructure induced by WAAM and its impact on the hot deformation behavior are analyzed. The results show that the proposed processing route appears to allow for similar properties as conventional forging process chains, but may reduce the number of processing steps and increase the material yield.

Additively manufactured (AM) components often exhibit significant discontinuities and indications without a clear understanding of how they might affect the mechanical properties of a part during qualification and service. This uncertainty is unacceptable for the design and manufacturing of most aerospace components. Current research in both mechanical testing and nondestructive evaluation involves developing methods for characterizing and inspecting AM components as the use of such materials continues to rise. Although several AM manufacturing methods have been developed in recent decades, this paper focuses on AM production-ready processes for a direct metal laser sintering (DMLS) powder bed fusion machine and will provide background on Sandia National Laboratories’ research efforts in this area. Tensile bar samples manufactured using the DMLS powder bed fusion method were inspected in this study, and the results of ultrasonic spectroscopy for assessing internal flaws will be presented. A combination of material property evaluation, microstructural characterization, and nondestructive inspection techniques will also be described. The results obtained from these material evaluation methods assist in determining inspection limits and methods for qualifying AM materials.

A sandwich composite represents a special class of composite materials that is manufactured by bonding two thin but stiff faces to a low density and low strength but thick core. The distance between the skins given by the core increases the flexural modulus of the panel with a low mass increase, producing an efficient structure able to resist at flexural and buckling loads. The strength of sandwich panels depends on the size of the panel, skins material and number or density of the cells within it. Sandwich composites are used widely in several industries, such as aerospace, automotive, medical and leisure industries. The behavior of composite sandwich panels with different core designs under different impact velocities are analyzed in this paper by numerical simulations performed on sandwich panels. The modeling was done in ANSYS and the analysis was performed through LS-DYNA.A sandwich composite represents a special class of composite materials that is manufactured by bonding two thin but stiff faces to a low density and low strength but thick core. The distance between the skins given by the core increases the flexural modulus of the panel with a low mass increase, producing an efficient structure able to resist at flexural and buckling loads. The strength of sandwich panels depends on the size of the panel, skins material and number or density of the cells within it. Sandwich composites are used widely in several industries, such as aerospace, automotive, medical and leisure industries. The behavior of composite sandwich panels with different core designs under different impact velocities are analyzed in this paper by numerical simulations performed on sandwich panels. The modeling was done in ANSYS and the analysis was performed through LS-DYNA.

Nowadays polymers are commonly used in various applications, which make it difficult to avoid its usage even though it causes environmental problems. Natural fibers are best alternate to overcome the polymer based environmental issues. Natural fibers play an important role in developing high performing fully newline biodegradable green composites which will be a key material to solve environmental problems in future. In this paper deals the properties analysis of banana fiber is combined with epoxy resin in order to create a natural composite, which has special characteristics for aerospace applications. The objective of this paper is to investigate the characteristics of failure modes and strength of natural composite using experimental and numerical methods. The test specimen of natural composite has been fabricated as per ASTM standard, which undergoes tensile and compression tests using Tinius Olsen UTM in order to determine mechanical and physical properties. The reference model has been designed by CATIA, and then numerical simulation has been carried out by Ansys Workbench 16.2 for the given boundary conditions.Nowadays polymers are commonly used in various applications, which make it difficult to avoid its usage even though it causes environmental problems. Natural fibers are best alternate to overcome the polymer based environmental issues. Natural fibers play an important role in developing high performing fully newline biodegradable green composites which will be a key material to solve environmental problems in future. In this paper deals the properties analysis of banana fiber is combined with epoxy resin in order to create a natural composite, which has special characteristics for aerospace applications. The objective of this paper is to investigate the characteristics of failure modes and strength of natural composite using experimental and numerical methods. The test specimen of natural composite has been fabricated as per ASTM standard, which undergoes tensile and compression tests using Tinius Olsen UTM in order to determine mechanical and physical properties. The reference model has been designed by ...

This study aims to investigate hard to machine alloys used in many fields of aerospace industry like titanium, nickel and magnesium alloys after Abrasive Electrodischarge Grinding (AEDG) process using different current settings. This paper presents the results concerned measurements of morphology and surface geometrical structure of samples made of materials used in aircraft industry after different kind of AEDG processes. For this purpose the different kind of measurement devices like optical microscopes and profilometers have been applied. Also optimal parameters of these kind of machining processes, including electrical and mechanical conditions, have been depicted. After each of stage of AEDG machining it is possible to obtain various morphology and roughness of samples made of these superalloys which can be used in different kind of applications especially in aerospace industry. Elaborated AEDG process allows for very fast and accurate machining of hard to machine aircraft alloys and can reduce significantly energy consumption and cost of machining comparing to traditional subtractive manufacturing processes.

Nimonic super alloy are extensively used in the aerospace industry because of its unique properties. As they are quite costly and difficult to machine, the machining tool is easy to get worn. To solve the problem, an experiment was carried out on a numerical control slitting automatic lathe to analysis the tool wearing conditions and parts’ surface quality of nimonic super alloy GH2132 under different cutters. The selection of suitable cutter, reasonable cutting data and cutting speed is obtained and some conclusions are made. The excellent coating tool, compared with other hard alloy cutters, along with suitable cutting data will greatly improve the production efficiency and product quality, it can completely meet the process of nimonic super alloy GH2312.

This paper describes the results of an experimental investigation aimed to st udy the machinability of AA7075 T6 (160 HV) for aerospace industry at high cutting speeds. The paper investigates the effects of different lubri-cooling strategies (cryogenic, M QL and dry) during high speed turning process on cutting forces, tool wear, chip morphology and cutting temperatures. The cutting speeds selected were 1000m/min, 1250m/min and 1500 m/min, while the feed rate values used were 0.1mm/rev and 0.3 mm/rev. The results of cryogenic and M QL application is compared with dry application. It was found that the cryogenic and M QL lubri-cooling techniques could represent a functional alternative to the common dry cutting application in order to implement a more effect ive high speed turning process. Higher cuttingparameters would be able to increase the productivity and reduce the production costs. The effects of the cutting parameters and on the variables object of study were investigated and the role of the different lubri-cooling conditions was assessed.

Modern aerospace industry is migrating from reactive to proactive and predictive maintenance to increase platform operational availability and efficiency, extend its useful life cycle and reduce its life cycle cost. Multiphysics modeling together with data-driven analytics generate a new paradigm called “Digital Twin.” The digital twin is actually a living model of the physical asset or system, which continually adapts to operational changes based on the collected online data and information, and can forecast the future of the corresponding physical counterpart. This paper reviews the overall framework to develop a digital twin coupled with the industrial Internet of Things technology to advance aerospace platforms autonomy. Data fusion techniques particularly play a significant role in the digital twin framework. The flow of information from raw data to high-level decision making is propelled by sensor-to-sensor, sensor-to-model, and model-to-model fusion. This paper further discusses and identifies the role of data fusion in the digital twin framework for aircraft predictive maintenance.Modern aerospace industry is migrating from reactive to proactive and predictive maintenance to increase platform operational availability and efficiency, extend its useful life cycle and reduce its life cycle cost. Multiphysics modeling together with data-driven analytics generate a new paradigm called “Digital Twin.” The digital twin is actually a living model of the physical asset or system, which continually adapts to operational changes based on the collected online data and information, and can forecast the future of the corresponding physical counterpart. This paper reviews the overall framework to develop a digital twin coupled with the industrial Internet of Things technology to advance aerospace platforms autonomy. Data fusion techniques particularly play a significant role in the digital twin framework. The flow of information from raw data to high-level decision making is propelled by sensor-to-sensor, sensor-to-model, and model-to-model fusion. This paper further discusses and identifies the ...

In the aerospace industry the demand for very strong and light components is a permanent objective. Composites have been used in manufacturing of aircraft and turbofans for decades. This is happening due to the high strength and low density of carbon fiber epoxy composites (~1.5g/cm3) in comparison with the lightest metallic alloys as magnesium alloys (~1.8g/cm3). Although in our days technology of carbon fiber epoxy composites reached a top level through manufacturing of fan blades for or ultra-high bypass turbofans, there is a room for improvement for important reduction of average density of components made of composites. This paper shows that using a bionic technology imitating the bird’s bone structure is possible for manufacturing of very light fan blades, fan vanes or fan housings having average densities smaller by several times than the compact composite materials. This technology can lead to manufacturing of very light turbofans or propfans which are the preferred propulsion systems for present aircraft.

Thin metal sheets are widely used to fabricate a various type of aerospace structures because of its flexibility and easily to form into any type shapes of structure. The riveted joint has turn out to be one of the popular joint types in jointing the aerospace structures because they can be easily be disassembled, maintained and inspected. In this paper, thin metal sheet components are assembled together via riveted joints to form a simplified model of aerospace structure. However, to model the jointed structure that are attached together via the mechanical joints such as riveted joint are very difficult due to local effects. Understandably that the dynamic characteristic of the joined structure can be significantly affected by these joints due to local effects at the mating areas of the riveted joints such as surface contact, clamping force and slips. A few types of element connectors that available in MSC NATRAN/PATRAN have investigated in order to presented as the rivet joints. Thus, the results obtained in term of natural frequencies and mode shapes are then contrasted with experimental counterpart in order to investigate the acceptance level of accuracy between element connectors that are used in modelling the rivet joints of the riveted joints structure. The reconciliation method via finiteelement model updating is used to minimise the discrepancy of the initial finite element model of the riveted joined structure as close as experimental data and their results are discussed.

Friction riveting is a new technique which finds its applications in a variety of domains, where there is a need to join dissimilar materials for the sake of achieving weight reduction of the components produced especially in the fields of aerospace and automobile. In this present work, a numerical simulation on the heat transfer analysis has been done to predict the variation of temperature on the surface of the components being joined. Owing to the applications, Aluminum rivet is chosen for friction riveting on Poly Methyl Metha Acrylate base material. Abaqus explicit version 6.14 has been used to simulate the results of the process. Heat flux at the joint interface has been computed and thermal distribution at the work material is predicted.Friction riveting is a new technique which finds its applications in a variety of domains, where there is a need to join dissimilar materials for the sake of achieving weight reduction of the components produced especially in the fields of aerospace and automobile. In this present work, a numerical simulation on the heat transfer analysis has been done to predict the variation of temperature on the surface of the components being joined. Owing to the applications, Aluminum rivet is chosen for friction riveting on Poly Methyl Metha Acrylate base material. Abaqus explicit version 6.14 has been used to simulate the results of the process. Heat flux at the joint interface has been computed and thermal distribution at the work material is predicted.

Stelia Aerospace company is specialized in the forming of small (Lmax 1000 mm) sheets for the aerospace industry. In order to diversify the production facilities of Stelia Aerospace we evaluated the capacity of the magnetic pulse forming to produce small parts. The material used is the aluminum alloy 2024-T4. The sheets used have a thickness of 1 mm, 2 mm and 1.6 mm. Stelia Aerospace manufactures more than 100 different small parts but they are all made up of a limited set of elementary geometries. These elementary geometries include: straight and interrupted straight fallen edges, concave and convex fallen edges, fallen edges holes and joggling. In this paper we present the work we have done to develop forming tools for one of these elementary geometries, the straight fallen edge. Special attention is paid to the geometric and metallurgic quality of parts. In order to evaluate dimensional reproducibility of the process, smalls series of parts were produced.

Aerial vehicles have become indispensable. There are in this field UAV (Unconventional Aerial vehicle) and transportation airplanes and other aerospace vehicles for spatial tourism. Today, the research and development activity in aerospace industry is focused to obtain a good and efficient design for airplanes, to solve the problem of high pollution and to reduce the noise. For these goals are necessary to realize light and resistant components. The aerospace industry products are, generally, very complex concerning geometric shapes and the costs are high, usually. Due to the progress in this field (products obtained using FDM) was possible to reduce the number of used tools, welding belts, and, of course, to eliminate a lot of machine tools. In addition, the complex shapes are easier product using this high technology, the cost is more attractive and the time is lower. This paper allows to present a few aspects about FDM technology and the obtained structures using it, as follows: computer geometric mode...

The electron beam additive manufacturing process with wire is a part of global trend to find fast and efficient methods for producing complex shapes elements from costly metal alloys such as stainless steels, nickel alloys, titanium alloys etc. whose production by other conventional technologies is unprofitable or technically impossible. Demand for additive manufacturing is linked to the development of new technologies in the automotive, aerospace and machinery industries. The aim of the presented work was to carried out research on electron beam additive manufacturing with a wire as a deposited (filler) material. The scope of the work was to investigate the influence of selected technological parameters such as: wire feed rate, beam current, travelling speed, acceleration voltage on stability of the deposition process and geometric dimensions of the padding welds. The research revealed that, at low beam currents, the deposition process is unstable. The padding weld reinforcement is non-uniform. Irregularity of the width, height and straightness of the padding welds can be observed. At too high acceleration voltage and beam current, burn-through of plate and excess penetration weld can be revealed. The achieved results and gained knowledge allowed to produce, based on EBAM with wire process, whole structure from stainless steel.

Additive Manufacturing (AM) processes offer the potential for manufacturing cost savings and rapid insertion into service through production of near net shape components for complicated structures. Use of these parts in high reliability applications such as those in the aerospace industry will require nondestructive characterization methods to ensure post-process material quality in as-built condition. Ultrasonic methods can be used for this quality verification. Depending on the application, the service life of AM components can be sensitive to the part surface condition. The surface roughness and layered structure inherent to the electron-beam powder-bed fusion process necessitates new approaches to evaluate subsurface material integrity in its presence. Experimental methods and data analytics may improve the evaluation of as-built additively manufactured materials. This paper discusses the assessment of additively manufactured EBM Ti-6Al-4V panels using ultrasonic methods and the data analytics applied to evaluate material integrity. The assessment was done as an exploratory study as the discontinuities of interest in these test samples were not known when the measurements were performed. Water immersion ultrasonic techniques, including pulse-echo and through transmission with 10 MHz focused transducers, were used to explore the material integrity of as-built plates. Subsequent destructive mechanical tests of specimens extracted from the plates provided fracture locations indicating critical flaws. To further understand the effect of surface-roughness, an evaluation of ultrasonic response in the presence of as-built surfaces and with the surface removed was performed. The assessment of additive manufactured EBM Ti-6Al-4V panels with ultrasonic techniques indicated that ultrasonic energy was attenuated by the as-built surface roughness. In addition, feature detection was shown to be sensitive to experimental ultrasonic parameters and flaw morphology.Additive Manufacturing (AM) processes offer the potential for manufacturing cost savings and rapid insertion into service through production of near net shape components for complicated structures. Use of these parts in high reliability applications such as those in the aerospace industry will require nondestructive characterization methods to ensure post-process material quality in as-built condition. Ultrasonic methods can be used for this quality verification. Depending on the application, the service life of AM components can be sensitive to the part surface condition. The surface roughness and layered structure inherent to the electron-beam powder-bed fusion process necessitates new approaches to evaluate subsurface material integrity in its presence. Experimental methods and data analytics may improve the evaluation of as-built additively manufactured materials. This paper discusses the assessment of additively manufactured EBM Ti-6Al-4V panels using ultrasonic methods and the data analytics applied...

The need of a continuously increasing size and performance of aerospace structures has settled the composite materials as the preferred materials in aircraft structures. Apart from the clear capacity to reduce the structural weight and with it the manufacture cost and the fuel consumption while preserving proper airworthiness, the prospect of tailoring a structure using the unique directional stiffness properties of composite materials allows an aerospace engineer to optimize aircraft structures to achieve particular design objectives. This paper presents a brief review of what is known as the aeroelastic tailoring of airframes with the intent of understanding the evolution of this research topic and at the same time providing useful references for further studies.

The use of additive manufacturing processes keeps growing in aerospace and biomedical industry. Among the numerous existing technologies, the Electron Beam Melting process has advantages (good dimensional accuracy, fully dense parts) and disadvantages (powder handling, support structure, high surface roughness). Analyzes of the surface characteristics are interesting to get a better understanding of the EBM operations. But that kind of analyzes is not often found in the literature. The main goal of this study is to determine if it is possible to improve the surface roughness by modifying some parameters of the process (scan speed function, number of contours, order of contours, etc.) on samples with different thicknesses. The experimental work on the surface roughness leads to a statistical analysis of 586 measures of EBM simple geometry parts.

Ti6Al4V or Grade 5 titanium alloy is widely used in the aerospace, medical, automotive and fabrication industries, due to its distinctive combination of mechanical and physical properties. Ti6Al4V has always been perverse during its machining, strangely due to the same mix of properties mentioned earlier. Ti6Al4V machining has resulted in shorter cutting tool life which has led to objectionable surface integrity and rapid failure of the parts machined. However, the proven functional relevance of this material has prompted extensive research in the optimization of machine parameters and cutting tool characteristics. Cutting tool geometry plays a vital role in ensuring dimensional and geometric accuracy in machined parts. In this study, an experimental investigation is actualized to optimize the nose radius and relief angles of the cutting tools and their interaction to different levels of machining parameters. Low elastic modulus and thermal conductivity of Ti6Al4V contribute to the rapid tool damage. The impact of these properties over the tool tips damage is studied. An experimental design approach is utilized in the CNC turning process of Ti6Al4V to statistically analyze and propose optimum levels of input parameters to lengthen the tool life and enhance surface characteristics of the machined parts. A greater tool nose radius with a straight flank, combined with low feed rates have resulted in a desirable surface integrity. The presence of relief angle has proven to aggravate tool damage and also dimensional instability in the CNC turning of Ti6Al4V.

The use of composite materials nevertheless is getting more prominent. The combination of reinforcing fibers and matrices will produce the desired strength orientation, tailorability and not to mention the complex shape that is hard to form on metallic structure. The weight percentage of composite materials used in aerospace, civil, marine etc. has increased tremendously. Since composite are stacked together, the possibility of delamination and/disbond defects are highly present either in the monolithic or sandwich structures. Tap test is the cheapest form of nondestructive test to identify the presence of this damage. However, its inconsistency and wide area of coverage can reduce its effectivity since it is carried out manually. The indigenous automated tap tester known as KETOK was used to detect the damage due to trapped voids and air pockets. The mechanism of detection is through controlling the tapping on the surface automatically at a constant rate. Another manual tap tester RD-3 from Wichitech Industries Inc. was used as reference. The acquired data was translated into damage profiling and both results were compared. The results have shown that the indigenous automated tester can profile the damage better when compared with the existing tap tester. As a conclusion, the indigenous automated tap tester has a potential to be used as an IN-SITU damage detection tool to detect delamination and disbond damage on composite panel. However, more conclusive tests need to be done in order to make the unit available to conventional users.

Additive manufacturing is a relatively young technology that uses the principle of layer by layer addition of material in solid, liquid or powder form to develop a component or product. The quality of additive manufactured part is one of the challenges to be addressed. Researchers are continuously working at various levels of additive manufacturing technologies. One of the significant powder bed processes for met als is Selective Laser Melting (SLM). Laser based processes are finding more attention of researchers and industrial world. The potential of this technique is yet to be fully explored. Due to very high strength and creep resistance Inconel is extensively used nickel based super alloy for manufacturing components for aerospace, automobile and nuclear industries. Due to law content of Aluminum and Titanium, it exhibits good fabricability too. Therefore the alloy is ideally suitable for selective laser melting to manufacture intricate components with high strength requirements. The selection of suitable process for manufacturing for a specific component depends on geometrical complexity, production quantity, and cost and required strength. There are numerous researchers working on various aspects like metallurgical and micro structural investigations and mechanical properties, geometrical accuracy, effects of process parameters and its optimization and mathematical modeling etc. The present paper represents a comprehensive overview of selective laser melting process for Inconel group of alloys.

According to the requirements of real-time, reliability and safety for aerospace experiment, the single center cloud computing technology application verification platform is constructed. At the IAAS level, the feasibility of the cloud computing technology be applied to the field of aerospace experiment is tested and verified. Based on the analysis of the test results, a preliminary conclusion is obtained: Cloud computing platform can be applied to the aerospace experiment computing intensive business. For I/O intensive business, it is recommended to use the traditional physical machine.

Use of full-matrix capture (FMC), combined with the total focusing method (TFM), has been shown to provide improvements to flaw sensitivity within components of irregular geometry. Ultrasonic immersion inspection of aerospace discs requires strict specifications to ensure full coverage – one of which is that all surfaces should be machined flat. The ability to detect defects through curved surfaces, with an equivalent sensitivity to that obtained through flat surfaces could bring many advantages. In this work, the relationship between surface curvature and sensitivity to standard defects was quantified for various front wall radii. Phased array FMC immersion inspection of curved components was simulated using finite element modelling, then visualized using surface-compensated focusing techniques. This includes the use of BRAIN software developed at the University of Bristol for production of TFM images. Modelling results were compared to experimental data from a series of test blocks with a range of curvatures, containing standard defects. The sensitivity to defects is evaluated by comparing the performance to conventional methods. Results are used to highlight the benefits and limitations of these methods relating to the application area of aerospace engine disc forgings.

Now a days the use of ti-6al-4v alloy is high in demand in many industries like aero space, bio medical automobile, space, military etc. the production rates in the industries are not sufficient because the machiniability of ti-6al-4v is the main problem, there are several cutting tools available for metal cutting operations still there is a gap in finding the proper cutting tool material for machining of ti-6al-4v. because the properties of titanium like high heat resistant, low thermal conductivity, low weight ratio, less corrosiveness, and more many properties attracting the industrialists to use titanium as their material for their products, many researchers done the research on machininbility of ti-6al-4v by using different tool materials. but as for my literature survey there is still lot of scope is available, to find better cutting tool with techniques for machining ti-6al-4v. in this paper iam discussing the work done by various researchers on ti-6al-4v alloy with different techniques.