Aging Behavior of T91/10CrMo910 Dissimilar Steel Welded Joints

The microstructure and property of T91/10CrMo910 dissimilar steel welded joints after one and two years service have been studied by OM, TEM, EDS and Vickers hardness test in this paper. The results showed that after one year service the microhardness of T91/10CrMo910 dissimilar steel welded joints increased clearly and after two years service chromium element diffused or transferred from the welding line or T91 matrix to 10CrMo910 matrix. Coarse lath martensite was the characteristic of the microstructure of T91/10CrMo910 dissimilar steel welded joints, and the martensite laths became fragment after one and two years service. More carbide particles had been observed after one year service than that after two year service, which had a good agreement with the results of the micro-Vickers hardness test.