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Growing demands for fuel efficient vehicles and reducing air pollution leads to light weighting of vehicles. Using optimum combination of high strength steel and lightweight aluminum alloy in the automotive structures may be answer to the problem. Joining of these two dissimilar metals have several issues related to techniques and reliability that need to be addressed for efficient mass production. There are several joining techniques used for dissimilar metals out of which Cold Metal transfer (CMT) is one of the methods. As simulation is an integral part of product design, development of CAE methodology for joining of dissimilar metals using CMT is necessary. This paper includes investigation on various modeling methods of welded joint developed using CMT process. Numbers of lap shear specimen were tested experimentally and results were compared with simulation. Based on correlation, most suited modeling technique was adopted.

The present work involves systematic study on identification of process parameters and processing conditions for effective laser surface-hardening of automotive crankshaft and its implementation in the industry, utilizing a diode laser integrated to a 6-axis robot and a turn/tilt table. The crankshaft chosen was made of low-alloyed 0.52% C steel and required hardening at two contact regions of bearing/flange seat areas and a pin area (on a different axis than the actual shaft). The subjected areas had features like oil holes, sharp corners and wide areas. The target was to develop laser hardening process resulting in hardened case-depth of above 200 µm with a hardness of 500 - 650 HV at different locations mentioned. Additionally, It was targeted to minimize the processing time and also eliminate any post process machining operations.