Enhancing the Mechanical and Metallurgical Behavior of Post-Processing on Friction Stir Processed AA8011 with NiTi-SMAs and Si3N4 Surface Hybrid Composites 2020-28-0419
This limited research was extended to study the modification surface amendment of materials through Friction Stir Process (FSP) with nanoparticle addition followed by the post-processing method. In this paper, strengthened the surface and core properties of AA8011 by adding nanoparticles such as Nitinol Shape Memory Alloy (NiTi-SMAs) and Silicon Nitride (Si3N4) through FSP followed by three different way of post-processing techniques like case hardening, case harden with the shot peening and laser peening. During FSP the use of NiTi-SMAs and Si3N4 as reinforcement interlocked the grains in nanocomposites of the processed zone. In addition, Post-processing promises a performance enhancement of core and surface hardness, ultimate tensile strength, impact and homogenizing their microstructure which is observed through scanning electron microscopic observations.The study has revealed that the laser peening surface has preferably higher performance than other post-processing techniques. Laser peening has a great impact on induced compressive residual stress with absents of crack closure. This techiqnique also improves significantly the fatigue life of the material while loading. The strengthening phase was uniformly distributed in grain or grain boundary and Also the hardened layer was evaluated using surface integrity with metallography study. On the whole, it was concluded that the coupled effect of reinforcement addition and laser peening technique was the best choice in augmenting demanded industries.