Hardness and Thermal Analysis in Welded Butt Joint of Hybrid Aluminium (LM25) Metal Matrix Nano Composite Cylindrical Rod using TIG Welding Process

An attempt is made in optimization of welding parameters of Hybrid LM25 Aluminium Metal Matrix Nano Composite (AMMNC) Cylindrical Rod made by using stir casting method. 2% of nano Silicon carbide (SiC) particles along with 3% of nano alumina is added with Base metal LM25 Aluminium alloy for producing Hybrid AMMNC Samples. Joining of this Hybrid AMMNC samples are done by using TIG welding Process. By conducting experiment, effect of welding parameters such as welding pulse current, Arc Voltage and shielding gas flow rate on welded Hybrid AMMNC Samples are studied. To develop the regression equation and predict the weld centre micro hardness value on welded AMMNC Samples Design-Expert version 11 statistical software is used. From the predicted value of weld centre micro hardness value 100HV has been observed from the Empirical model results. Therefore to optimize welding pulsed current, Arc Voltage and Shielding gas flow rate parameters are resulted in higher micro hardness value as observed in welded Hybrid AMMNC Samples ,which implies that strength of the weld is increased with respect to optimize welding parameters. In addition to investigate the temperature distribution in optimized Hardness value of welded AMMNC sample. Then heat fusion in the size and distribution of heat source, the travel speed, the heat conduction in the welding direction and the surface heat loss during welding are considered. A numerical scheme is developed to solve the three dimensional problem. With the help of a mathematical model, the effect of welding parameters such as heat input of the weld, preheating of the work piece and moving velocity of heat source on weld penetration in welded AMMNC cylindrical rod samples are discussed. The steadystate temperature profiles of the welded AMMNC samples are solved by finite difference method. In addition, a thermal experiment such as Heat Flux Differential Scanning Calorimeter Experiment is conducted to verify the theoretical results and Numerical results in ANSYS software. The predicted values from the proposed model are compared with the experimental data of optimized welded AMMNC samples.