Effect of Post Weld Heat Treatment on Welds in Steel Structures

摘要

The effect of post weld heat treatment (PWHT) on residual stresses, yield strength and toughness as well as on microstructural features of submerged arc weld metal was studied with three types of C-Mn-steels. All techniques used for measuring residual stress reduction in PWHT are found to be insufficient to adequately characterize the stress distribution. The yield and ultimate strength are not significantly affected by the PWHT (600 C/2 hr) applied. No improvement in the toughness as determined by the COD is found. Slight coarsening of the microstructure is, however, observed. With the submerged arc welding method no advantages of PWHT can be expected other than reduced risk to brittle fracture through stress relief.