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The purpose of this paper is to study formability, tensile properties, dislocation density and surface roughness of incrementally deformed Ti–6Al–4V alloy sheets during single-point incremental forming (SPIF) and multi-point incremental forming (MPIF) process. The development of corrosion pits in 3.5% NaCl solution has also been studied during SPIF and MPIF processes.

In this study, the formability, tensile properties, dislocation density, surface roughness and corrosion behaviour of deformed Ti–6Al–4V alloy sheets were studied. A potentio-dynamic polarization (PDP) study was conducted to study the corrosion behaviour of Ti–6Al–4V alloy samples during SPIF and MPIF processes and the results were also compared with base material (BM) in 3.5% NaCl solution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses were carried out to study the corrosion morphology and dislocation densities of deformed samples.

The deformed Ti–6Al–4V alloy sheets obtained higher plastic deformation, high tensile strength, good surface roughness and good corrosion resistance during MPIF process when compared with SPIF process.

It has been concluded that the maximum strain and good corrosion resistance have been achieved with MPIF process, which in turn increases the plastic deformation as compared with BM.

This study discussed the formability, tensile properties, surface roughness and corrosion behaviour of deformed Ti–6Al –4V alloy sheets during incremental sheet forming (ISF) process.

This study is useful in the field of medical, industrial and automobile applications.

The Ti–6Al–4V alloy is deformed using MPIF process, achieving better formability, tensile strength, good surface roughness and corrosion rate, and the same is evidenced in forming limit diagrams (FLDs) and PDP curves.

The purpose of this paper is to consider the corrosion properties of laser nitrided Ti‐6Al‐4V alloys that have been reported previously by several researchers.

Different kinds of surface nitriding methods of titanium alloys, such as plasma nitriding, ion nitriding, gas and laser nitriding, are introduced. Microstructure changes, such as phase formation and the influence of laser processing parameters in laser nitriding layers of Ti‐6Al‐4V alloys, were investigated using scanning electron microscope, transmission electron microscope, X‐ray photo‐electron spectroscopy, and X‐ray diffraction. Based on investigations presented in the literature, the effect of laser nitriding on the corrosion behavior of Ti‐6Al‐4V alloy was reviewed.

By regulating the laser processing parameter, the microstructure of the nitrided layer can be controlled to optimize corrosion properties. This layer improves corrosion behavior in most environments, due to the formation of a continuous TiNxOy passive film, which can retard the ingress of corrosive ions into the substrate and can maintain a constant value of a current density. Therefore, the laser gas nitrided specimens have a relatively noble corrosion potential and a very small corrosion current, as compared to untreated specimens.

This paper comprises a critical review, and its collection of references is useful. It summarizes current knowledge in laser surface treatment research.

Titanium (Ti) alloys are in high demand in manufacturing industries all over the world. The property like high strength to weight ratio makes Ti alloys highly recommended for aerospace industries. Ti alloys possess good weldability, and therefore, they were extensively investigated with regard to strength and metallurgical properties of welded joint. This study aims to deal with the analysis of strength and microstructural changes in Ti-6Al-4V (Grade 5) alloy after tungsten inert gas (TIG) welding.

Two pair of Ti alloy plates were welded in two different voltages, i.e. 24 and 28 V, with keeping the current constant, i.e. 80 A It was a random selection of current and voltage values to check the performance of welded material. Both the welded plates were undergone through some mechanical property analysis like impact test, tensile test and hardness test. In addition, the microstructure of the welded joints was also analyzed.

It was found that hardness and tensile properties gets improved with an increment in voltage, but this effect was reverse for impact toughness. A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this work. Heat distribution in both the welded plates was simulated through ANSYS software to check the temperature contour in the plates.

A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this study.

In friction welding of dissimilar joint method, few material compositions are not possible to weld effectively. For better dissimilar metal joining in friction welding, the interlayer techniques are used by the third metal to increase the diffusion for suitable metal bonding. The interlayer metals are popularly held by coating, foils, sheet and solid rod form. The coating method needs more care for surface preparation with special coating equipment with high workmanship. In case of foil as intermediate metal, more care is neededfor holding between the metal; most of the time this technique has the possibility of failure by peeling off from the contact surface during high speed rotation with pressure during friction generation.

In this investigation, a copper coin was machined to a suitable size (transition fit) to suit the recess inside the SS rod. The mating surfaces of Cu coin, SS rod and Ti alloy were machined, polished to mirror finish and handled in friction welding machine. The purpose of the transition fit between the coin and SS rod is for holding the same intact before the beginning of the process.

Successful joint was achieved with good joint strength at less time. Empirical models were established to fin out the joint strength at any given parameter within the range of investigation

The models developed can be used only within the range of investigation considered for experimentation.

The paper includes implications for the development of a method of joining any dissimilar joints

In this investigation, a copper coin was machined to a suitable size (transition fit) to suit the recess inside the SS rod. The mating surfaces of Cu coin, SS rod and Ti alloy were machined, polished to mirror finish and handled in friction welding machine. The purpose of the transition fit between the coin and SS rod is for holding the same intact before the beginning of the process.

This paper focuses on recent advances in direct freeform fabrication of high performance components via selective laser sintering (SLS). The application, known as SLS/HIP, is a low cost manufacturing technique that combines the strengths of selective laser sintering and hot isostatic pressing (HIP) to rapidly produce low volume or “one of a kind” high performance metal components. Direct selective laser sintering is a rapid manufacturing technique that can produce high density metal parts of complex geometry with an integral, gas impermeable skin. These parts can then be directly post‐processed by containerless HIP. The advantages of in situ encapsulation include elimination of a secondary container material and associated container‐powder interaction, reduced pre‐processing time, a short HIP cycle and reduction in post‐processing steps compared to HIP of canned parts. SLS/HIP is currently being developed under a DARPA/ONR program for INCONEL® 625 superalloy and Ti‐6Al‐4V, the demonstration components being the F‐14 turbine engine vane and the AIM‐9 missile guidance section housing base respectively.

The purpose of this paper is to study the effect of ultrasonic machining process parameters on surface quality while machining titanium alloy Ti-6Al-4V.

Effect of cryogenic treatment (CT) of tool and work material was also explored in the study. Taguchi’s L18 orthogonal array was chosen for design of experiments and average surface roughness was measured.

Different modes of fracture were detected at work surface corresponding to varied input process parameters. Slurry grit size, power rating and tool material along with CT of work material were found to be the significant parameters affecting surface quality.

The results obtained have been modelled using artificial neural network approach.

Electron-beam welding has been widely used in industry to join different titanium alloys (Ti-6Al-4V) components. During welding production defects, such as porosity, lack of penetration or thinning are often observed. High-cycle fatigue (HCF) tests have been performed on welded specimens to understand the effect of weld defects on fatigue capabilities. The fatigue life of different types of “defective” welds has been compared against a non-welded reference specimen.

The results of the experimental campaign have been correlated with finite elements models.

It is concluded the geometry produced by the weld process, e.g. toe radius and under-bead shape, and the related stress raisers play a relevant role on fatigue capabilities of welds. This conclusion is valid only for a Ti-6Al-4V T-joint weld and only for flaw initiation. Knock down in materials properties has not been considered.

There is a lack of HCF fatigue data for welds of this geometry and material in the open literature. The paper is of relevance for industrial application and practical interest, although a lot more validation tests are required to draw a final conclusion.

The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding and polishing of additive titanium alloy blades to ensure the surface integrity and machining accuracy of the blades.

At present, robot grinding and polishing are mainstream processing methods in blade automatic processing. This review systematically summarizes the processing characteristics and processing methods of additive manufacturing (AM) titanium alloy blades. On the one hand, the unique manufacturing process and thermal effect of AM have created the unique processing characteristics of additive titanium alloy blades. On the other hand, the robot grinding and polishing process needs to incorporate the material removal model into the traditional processing flow according to the processing characteristics of the additive titanium alloy.

Robot belt grinding can solve the processing problem of additive titanium alloy blades. The complex surface of the blade generates a robot grinding trajectory through trajectory planning. The trajectory planning of the robot profoundly affects the machining accuracy and surface quality of the blade. Subsequent research is needed to solve the problems of high machining accuracy of blade profiles, complex surface material removal models and uneven distribution of blade machining allowance. In the process parameters of the robot, the grinding parameters, trajectory planning and error compensation affect the surface quality of the blade through the material removal method, grinding force and grinding temperature. The machining accuracy of the blade surface is affected by robot vibration and stiffness.

This review systematically summarizes the processing characteristics and processing methods of aviation titanium alloy blades manufactured by AM. Combined with the material properties of additive titanium alloy, it provides a new idea for robot grinding and polishing of aviation titanium alloy blades manufactured by AM.

This paper aims to present a broad review of near-a titanium alloys for high-temperature applications.

Following a brief introduction of titanium (Ti) alloys, this paper considers the near-α group of Ti alloys, which are the most popular high-temperature Ti alloys developed for a high-temperature application, particularly in compressor disc and blades in aero-engines. The paper is relied on literature within the past decade to discuss phase stability and microstructural effect of alloying elements, plastic deformation and reinforcements used in the development of these alloys.

The near-a Ti alloys show high potential for high-temperature applications, and many researchers have explored the incorporation of TiC, TiB SiC, Y₂O₃, La₂O₃ and Al₂O₃ reinforcements for improved mechanical properties. Rolling, extrusion, forging and some severe plastic deformation (SPD) techniques, as well as heat treatment methods, have also been explored extensively. There is, however, a paucity of information on SiC, Y₂O₃ and carbon nanotube reinforcements and their combinations for improved mechanical properties. Information on some SPD techniques such as cyclic extrusion compression, multiaxial compression/forging and repeated corrugation and straightening for this class of alloys is also limited.

This paper provides a topical, technical insight into developments in near-a Ti alloys using literature from within the past decade. It also outlines the future developments of this class of Ti alloys.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.