Effect of post weld heat treatment on microstructure and hardness on CLAM steel TIG weld
1.School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Physics Department, University of Science and Technology of Beijing, Beijing 100083, China)
Abstract：China Low Activation Martensitic(CLAM) steel was buttwelded by tungsteninertgas welding. Post welding heat treatment(PWHT) was performed at different temperatures(610, 660, 710, 760, 810℃) for 30 min. There is great difference on microstructure and hardness of CLAM steel TIG weld before and after PWHT. With the rise of PWHT temperature, the distribution and size of martensitic lath are more uniform, especially above 710℃. But the size of crystal and the martensitic lath width are growing. PWHT made the hardness of the welding joint lower. The higher the post welding heat treatment temperature is, the lower the hardness results are.The hardness of weld metal decreased more than that of the heat affected zone and the base metal. When the PWHT temperature reached 810℃, the hardness of the weld material droped obviously, almost reaching the hardness of the base metal.
2010, Vol. 31 
