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ABSTRACTThere is high demand of Aluminium material for various engineering applications but the main problem being low wear and corrosion resistance. Laser beam application for surface modification of engineering materials gets high attention in research and industries due to superior surface performance for wear and corrosion resistance. In the present research article, an attempt has been made to improve the properties of Aluminium by laser surface alloying technology. Laser surface alloying of commercially pure aluminium with titanium and zinc metal powders at 50% combination has been conducted using CO2laser power from 1600 to 2000 W. The experiments have been planned through design of experiment using Response Surface Methodology (RSM). The mathematical modelling and optimisation of process parameters such as specific laser power scan speed and heat input for optimum value of Micro hardness has been carried out using RSM with three factors and five levels. The statistical significance of the data has been carried out using Analysis of Variance (ANOVA).The alloy made by Al-TiZn shows improved hardness by 47% due to good laser surface alloying which has created dendrite microstructure without any metallurgical defects. The optimised value of laser energy density was found to be 37 J/mm2. It has been investigated that the optimum values of laser speed and heat input are 84 m/s and 61.50 watt respectively for micro hardness value of 56HV. Hardness decreases from top alloy zone towards substrate material since high energy creates more depth where the concentration of alloying elements is less. The friction coefficient of Al-TiZn alloy was found to be less by 23% than unalloyed aluminium substrate. The depth of laser alloyed has been increased with laser power and heat input from laser beam. Higher electron microscopy analysis shows that a sound alloying has been created without surface and subsurface defects. The present investigation is expected to help automobile and aerospace industries where the wear and corrosion resistance of the material are of major concern.

Metal-polymer-metal (MPM) sandwich composites are in the class of proficient engineering materials which give outstanding strength-to-weight ratios because of their comparatively low density. These materials are vital constituents within the automobile, aerospace, marine, and civil construction industries as substitutes for sheet metals that considerably reduce weight while not compromising functionality. Moreover, these materials have supplementary qualities like sound dampening and thermal insulation capabilities. For these materials to be utilized within the aforesaid industries, they need to bear numerous forming processes that are essential in product manufacturing. This paper investigated formability analysis of metal-polymer sandwich composites made of “AW 6082-PVC-AW 6082 (APA)” and “galvanized steel-PVC-galvanized steel (GPG)” sandwich sheets, considering epoxy structural adhesives as the binding agent, via FEA simulation. All the FEA simulations were performed using Altair HyperWorks software. For evaluating the formability, the actual limit dome height (LDH)—biaxial strain path—tests were simulated using FEM software. The results analyzed are forming limit diagram (FLD), punch force distribution, and a dome height at diverse conditions of punch velocity and friction. A comparison is made to represent the best combinations for formability of the sandwich composites. Maximum formability and dome height are attained at low friction conditions and forming speed. It has also been observed that LDH simulations are very sensitive to friction, and it has a substantial impact on the test outputs. Maximum thinning (or fracture) generally moves away from the apex of the dome towards the die corner radius as the friction increases from zero upwards.