Heat treatment and post weld for steel and its alloys

Post weld heat treatment (PWHT) defined as any heat treatment after welding, is often used to improve the properties of a weldment. In concept, PWHT can encompass many different potential treatments. PWHT can be used to reduce residual stresses, as a method of hardness control, or even to enhance material strength. If PWHT is performed incorrectly, or neglected altogether, residual stresses can combine with load stresses to exceed a material’s design limitations. This can lead to weld failures, higher cracking potential, and increased susceptibility to brittle fracture.