Influences of Vanadium and Copper on Microstructure and High-Temperature Mechanical Properties of 11Cr-2W Low Activation Martensite Steel

The influences of vanadium contents and 0.22wt.%Cu on microstructure and tensile and creep properties at 650 ℃ of an 11Cr-2W low activation martensite steel were studied. The results show that vanadium contents and 0.22wt.%Cu had obvious effects on microstructure and the size of M23C6 phase. When the mass fraction of vanadium was 0.105%,MX phase diffusely distributed in the matrix,and now the phase owned the largest number and smallest size. The tensile strength of the tested steel increased from 325.2 MPa to 289.4 MPa,and the creep-rupture life decreased from 370 h to 251 h when the mass fraction of vanadium increased from 0.105wt.% to 0.203wt.%. The creep-rupture life of the tested steel could be increased by adding 0.22wt.%Cu.