Superior creep resistance of a high-Cr steel with Re additives

Abstract Re-containing 10Cr-3Co-3W martensitic steel with low nitrogen and high boron contents exhibited a rupture time of 10,987 h at 650 °C/140 MPa. This superior creep resistance was caused by partially saved tempered martensite lath structure due to precipitation of M23C6 carbides and Laves phase chains on lath boundaries as well as their high resistance to coarsening. M23C6 carbides were characterized by decreased interfacial energy that resulted in the retention of the orientation relationship between M23C6 carbides and ferritic matrix. Re slowed down diffusion of W, Mo and Cr atoms.