Q. Residual stresses in steel after welding?

Considerable residual stresses are persuaded in connecting steel members after welding operation. Local temperature of steel where welding occurs is higher than the remaining parts of the connecting steel members. This causes thermal expansion locally at the time of welding and subsequent contraction after welding. Tensile stresses associated with thermal contraction produced at the time of cooling process are balanced by compressive stresses in remaining parts of connecting steel members. Consequently residual stresses are persuadedat the time of welding operation.