Friction Stir Spot Welding-Brazing of Al and Hot-Dip Aluminized Ti Alloy with Zn Interlayer

Friction stir spot welding (FSSW) of Al to Ti alloys has broad applications in the aerospace and automobile industries, while its narrow joining area limits the improvement of mechanical properties of the joint. In the current study, an Al-coating was prepared on Ti6Al4V alloy by hot-dipping prior to joining, then a Zn interlayer was used during friction stir joining of as-coated Ti alloy to the 2014-Al alloy in a lap configuration to introduce a brazing zone out of the stir zone to increase the joining area. The microstructure of the joint was investigated, and the joint strength was compared with the traditional FSSW joint to confirm the advantages of this new process. Because of the increase of the joining area, the maximum fracture load of such joint is 110% higher than that of the traditional FSSW joint under the same welding parameters. The fracture load of these joints depends on the joining width, including the width of solid-state bonding region in stir zone and brazing region out of stir zone.

Tribological Behaviour and Metallographic Study of Al 2014 Alloy Reinforced by SiC Particle

The MMC pins containing 10 wt. % particles with sizes of 45 μm and 110 m SiC particles, and its 2014 Al alloy, produced by liquid casting method were tested against abrasive papers under different conditions. Wear surfaces were examined to determine the possible wear mechanisms by Scanning Electron Microscope (SEM). The wear rate of the composite decreased slightly with increasing SiC particle sizes and increased with increasing load. Furthermore, SEM examination showed that few wear craters, oxidized debris particles were dominant for the composite. For lower loads, grooving and delaminating layer on the wear surface were effective for the matrix alloy. Smoothening mechanisms were also dominated for all three types of materials under higher loads as well.

Evolution of Microstructure and Crystallographic Texture in AA2014 Aluminium Alloy during Equal Channel Angular Extrusion

Present work addresses the evolution of texture and microstructure of equal channel angular extrusion (ECAE) processed AA 2014 Al alloy upto four passes at room temperature by adopting route BC. TEM is used to assess the microstructural changes during each ECAE pass. Texture measurements on samples of each pass were carried out by XRD technique. The evolution of texture components after each ECAE pass are analyzed and the changes are discussed with respect to the initial texture.