The Role of Microstructure in Creep Strength of 9-12%Cr Steels

Tempered martensite lath structure (TMLS) plays a vital role in creep resistance of high chromium martensitic steels. Under creep conditions the TMLS could be stabilized by three agents: (i) a dispersion of boundary M 23 C 6 carbides and Laves phase; (ii) a dispersion of M(C,N) carbonitrides, which are homogeneously distributed within ferritic matrix; (iii) substitutional alloying element within ferritic matrix. The boundary particles exert a...