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Distortion is a severe problem in weld products.It depends on various process parameters like plate thickness, current, voltage, type of weld joint and restraints put on. If distortion is not properly dealt during welding then the product may become useless from geometric accuracy point of view. In the present study, a 3-D coupled transient thermal analysis model with auxiliary side heating (parallel heating) is developed to control angular distortion. During analysis, parallel heating flames are placed at several locations from weld line in cross direction. A user defined subroutine is used to apply transient heat source and side heating flames. Element birth and death technique is used to simulate the filler material deposition. One side multipass 'V' butt weld configuration is used for this study. A series of observational tests are done with a special experimental fixture using Manual Metal Arc Welding (MMAW) to validate the proposed FEA model. It is found that the angular distortion has decreased from 2 mm to 0.4 mm with change in side heating distance from 50 to 90 mm from the weld line.

This paper proposes a unique Al25Zn/SiC/Graphite hybrid composite for plain bearing and other wear-resistant applications. Newly synthesized composites of Al-25Zn alloy reinforced with 3 wt-% graphite and 10, 15 and 20 wt-% SiC are tested using a pin on the disc tribometer following ASTM G-99 standard against EN24 disc. Sliding wear studies using the Taguchi L 16 array are carried out for a set of parameters including pin temperature, speed, load and a constant sliding distance. The results reveal that adding 3 wt-% graphite into Al25Zn/SiC composites greatly enhances wear resistance, tensile strength, impact strength and ductility at the expense of hardness. The wear behaviour of the composites is predicted using an artificial neural network and a regression model. Adhesion is found the most common wear mechanism in matrix alloys, while abrasion and delamination in composites. Among the examined materials, the composite with 3 wt-% graphite and 15 wt-% SiC has the optimum combination of characteristics.