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Severe surface Plastic deformation plays a vital role in materials and several investigations are made on this route. Though, the influence of stacking fault energy of materials on severe surface plastic deformation is not done yet. This investigation studied the optimization of process parameter of SMTP with varying stacking fault energies on wear characteristics of AA6061 and ETP-Copper materials. Also, this investigation on reduction in the stacking fault energy contributes wear characterization were determined. The process parameters such as size of shots, speed of revolution of shaft and duration of treatment chosen which are directly associated to the energy imparted to the surface to induce high strains, accumulation of dislocations and grain refinement that leads to enhancement in strength of material surface. The predicted optimal vales of AA6061 are 4 mm shots, 750 rpm speed of revolution and 45 min duration and ETP-Copper are 4 mm shots, 500 rpm speed of revolution and 60 min duration. The wear volume loss of AA6061, a wear volume loss of 14.5854 × 10 −5 cm 3 is found, which 58% is lower than the wear volume loss of the untreated sample. The wear volume loss of ETP-Copper is 9.5366 × 10 −5 cm 3 , which is 58% lower than the wear volume loss of the untreated sample.

Laser shock peening is a well-known surface treatment process that dominates other modern surface treatment processes. Though several materials are investigated toenhance mechanical properties by LSP treatment, only a scarce number of studies have concentrated on Low Pulsed Laser Shock Peening (LPLSP) without an ablative layeron Aluminum Alloy 7075 T651 material. Thus this article investigates the optimization and effect of LPLSP on the mechanical behavior of AA 7075 T651. Grey Relational Analysis is chosen to optimize the Process Parameters on Low Pulsed Energy of LSP. The significant contributions of the optimized parameters on the mechanical behavior such as hardness, compressive residual stress, roughness and friction wear property are investigated. A drastic improvementof three times in the average hardness value occurred in LPLSP over the un-peened specimen. A maximum compressive residual stress is observed with the LPLSP specimen for the optimized parameters. An improvement of 65 % in the minimum wear rate was recorded in LPLSP compared to unpeened specimens. The microstructural studies carried outusing an optical microscope and scanning electron microscope show a typical grain refinement and increase in the boundary for LPLSP specimen.

Laser shock peening (LSP) is the emerging technology among several severe surface treatment processes for improving mechanical characteristics of metallic materials by producing compressive residual stresses. Though several LSP experiments have been done on compressive residual stresses, scare amount of studies concentrated on numerical investigation of residual stresses in LSP. The objective of this article is investigation of the experimental and numerical study of compressive residual stresses on AA 7075 t651. In the experiment, residual stresses analysis is performed. The sin^ method was utilized for measuring residual stresses. The three-dimensional (3-D) finite element method (FEM) analysis was applied to simulate the LSP on AA 7075 t651. The simulated and measured results showed good agreements. The numerical study was utilized to determine the compressive residual stresses.

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