Kush Mehta

A Review on Dissimilar Friction Stir Welding of Copper to Aluminum: Process, Properties, and Variants

Copper and aluminum materials are extensively used in different industries because of its great conductivities and corrosion resistant nature. It is important to join dissimilar materials such as copper and aluminum to permit maximum use of the special properties of both the materials. The joining of dissimilar materials is one of the most advanced topics, which researchers have found from last few years. Friction stir welding (FSW) technology is feasible to join dissimilar materials because of its solid state nature. Present article provides a comprehensive insight on dissimilar copper to aluminum materials joined by FSW technology. FSW parameters such as tool design, tool pin offset, rotational speed, welding speed, tool tilt angle, and position of workpiece material in fixture for dissimilar Cu–Al system are summarized in the present review article. Additionally, welding defects, microstructure, and intermetallic compound generation for Cu–Al FSW system have been also discussed in this article. Furthermore, the new developments and future scope of dissimilar Cu–Al FSW system have been addressed.

Effects of Tilt Angle on the Properties of Dissimilar Friction Stir Welding Copper to Aluminum

In the present investigation, dissimilar materials such as electrolytic tough pitch copper, and aluminum 6061-T651 were welded by friction stir welding technology. Effects of tool tilt angle on the mechanical and metallurgical properties were studied experimentally for dissimilar material systems. In the present study, the tool tilt angle was varied from 0° to 4° with an interval of 1°, while the other parameters such as rotational speed, welding speed, tool pin offset, and workpiece material position were kept constant. Macrostructure analysis, tensile test, macro hardness measurement, scanning electron microscopy, and energy dispersive x-ray spectrographic tests were performed to evaluate the weld properties of dissimilar copper–aluminum joints. The results revealed that a defect free dissimilar copper–aluminum friction stir welding was achieved by tilt angles 2°, 3°, and 4°. The maximum tensile strength was reported to be 117 MPa and the macro hardness was reported to be 181 VH (in the nugget zone) at a tilt angle of 4°. The macro hardness was increased as the tilt angle increases from 0° to 4°. In addition to this, the thermo-mechanically affected zone (at the copper side) was found to be the weakest zone for a dissimilar copper–aluminum friction stir welding system.

Influence of tool pin design on properties of dissimilar copper to aluminum friction stir welding

Abstract Dissimilar friction stir welding (FSW) of copper and aluminum was investigated by nine different tool designs, while the rest of the process parameters were kept constant. Mechanical and metallurgical tests such as macrostructure, microstructure, tensile test, hardness, scanning electron microscope and electron X-ray spectrographs were performed to assess the properties of dissimilar joints. The results exhibited that, the maximum joint strength was achieved by the tool of cylindrical pin profile having 8 mm pin diameter. Besides, the fragmental defects increased as the number of polygonal edges decreased, hence the polygonal pin profiles were unsuitable for dissimilar FSW butt joints. Furthermore, the tensile strength increased as the number of polygonal edges increased. Stir zone of polygonal pin profiles was hard and brittle relative to cylindrical tool pin profiles for same shoulder surface. Maximum hardness of HV 283 was obtained at weld made by the polygonal square pin profile. The hard and brittle intermetallic compounds (IMCs) were prominently presented in the stir zone. Phases of IMCs such as CuAl, CuAl 2 , Cu 3 Al and Cu 9 Al 4 were presented in the stir zone of dissimilar Cu–Al joints.

Advanced Joining and Welding Techniques: An Overview

Joining and welding is an essential component of manufacturing technology. New developments in joining and welding are evolved in order to acquire extraordinary benefits such as unique joint properties, synergistic mix of materials, cost reduction of component, increase productivity and quality, complex geometrical configurations, suitability and selection of material to manufacture new products. This chapter provides an update on recent developments of welding and joining to showcase above benefits. Theoretical background, process parameters, novel aspects, process capabilities, and process variants along with its application are presented in this chapter. Advanced welding and joining techniques are addressed under different headings of fastening and bonding processes, developments of arc welding processes, advanced beam welding techniques, sustainable welding processes, micro-nano joining and hybrid welding.

Hybridization of filler wire in multi-pass gas metal arc welding of SA516 Gr70 carbon steel

ABSTRACT In the present investigation, multi-pass gas metal arc welding (GMAW) of SA516 Gr70 carbon steel was carried out by different filler wires such as solid, metal cored and flux cored, wherein, other process parameters were kept constant. The hybrid approach of multi-pass filler wires was applied to obtain three different welds. The root pass was filled by a solid wire for all three cases while the subsequent filler pass was applied through solid, flux-cored and metal cored filler wires, respectively. Metallographic, mechanical and metallurgical analyses such as macrograph study, optical microscopy, tensile testing and hardness variations were performed to address the quality of weld. The results revealed that defect-free sound welds were produced by the hybrid approach of different filler wires in multi-pass GMAW. Overall cost and time reduction can be achieved through hybrid filler welds, without affecting their mechanical strength. Angular distortion was reported minimum at hybrid weld of solid and metal cored filler wire. Maximum reinforcement with higher penetration was observed at weld of solid and metal cored filler wire. Impact toughness was reported higher in case of hybrid weld of solid and flux cored filler wire. Higher macro hardness was reported at weld of solid and flux cored filler wire.

Nano-Machining, Nano-Joining, and Nano-Welding

This chapter sheds light on the role and use of nanotechnology in manufacturing. The theme of this chapter is basically focused on nano-machining, nano-joining and welding, and nano-EDM technologies exploited for the production of precision engineered parts and components to cater the need of increasing global trend of miniaturization. Major nano-techniques in the aforementioned manufacturing areas, their development, current trend, salient features, and applications are exclusively discussed in this chapter.

Welding and Joining of Shape Memory Alloys

Shape memory alloys are difficult to weld due to their own special properties, which lead to the problems of joints such as low strength, formation of intermetallic compounds, variations in phase transformation effects and its temperature, and changes of shape memory effect. However, different welding and joining processes are attempted to solve these problems. In this chapter, various welding processes such as tungsten inert gas welding, plasma welding, laser beam welding, electron beam welding, resistance welding, friction stir welding, friction welding, explosive welding, ultrasonic welding, diffusion bonding, adhesive bonding, brazing, and soldering are discussed on process capabilities and challenges to obtain shape memory welds.

Machining of Shape Memory Alloys

Shape memory alloys (SMAs) are considered as difficult-to-machine materials. This chapter sheds light on machinability aspects of SMAs and presents a comprehensive discussion on advanced and sustainable strategies and techniques for machining SMAs. It commences with an introduction to machinability, challenges of SMAs and possible solutions before discussing implementation of machining strategies and techniques to enhance machinability. The chapter ends with an outlook and selected avenues for possible future research capabilities of SMAs machining. As regards to the advanced machining of SMAs, the major focus of this chapter is on electric discharge (electric discharge), laser beam, and abrasive water jet machining. Whereas, in sustainable machining section, the use of advanced cooling and lubrication strategies during conventional turning, milling, drilling, and grinding of SMAs are emphasized. Some aspects of a recent experimental research conducted on MQL-assisted turning of NiTi shape memory alloy are also included in this chapter.

Processing of Shape Memory Alloys

Processing of shape memory alloys is attempted abundantly considering its numerous applications in different sectors of industries. However, it is not easy to process shape memory alloys as it has unique properties of pseudoelasticity, tendency to form intermetallic compounds, different phase transformation temperatures and deformation behavior. Different processing techniques reported for shape memory alloys such as powder metallurgy, additive processing, mechanical processing, and thermo-mechanical processing are considered in this chapter that addresses process condition, process parameters, and properties after processing.