Studies on the Wear and Change in Microstructure of Weld-Joint of a Structural Steel

The wear characteristics of a multi-pass weld-joint, of a low carbon- manganese structural steel has been studied together with the characteristics of its varying microstructure and hardness at different locations. Attempts have been made to correlate the wear characteristics with the varying microstructure and the varying hardness values in the weld-joint. It is observed that the wear characteristics, e.g. wear rate and coefficient o f wear resistance are considerably dependent only on the microstructure. The various sub zone microstructures observed in the weld metal and HAZ on a SA weld are spherodized, partially transformed; grain refined and grain coarsened area exhibiting predominantly Widmanstatten ferrite with pearlite, with the others sub zones of HAZ reveal polygonal ferrite and pearlite. Depending on the number, size and distribution of inclusions, the weld microstructure varies because of the prevalence of varying cooling rates in weld metal, a wide range of microstructures such as periodic pearlite, grain boundary ferrite with pearlite and side place with cementite along the side plate boundaries. This study has been performed to investigation on the wear of a weld joint of a structural steel and variations in the microstructure at various regions of heat affected zone base metal and a weld metal.