Formation of the reversed austenite during intercritical tempering in a Fe-13%Cr-4%Ni-Mo martensitic stainless steel

Formation of the reversed austenae obtained by intercritical tempering has been studied via transmission electron microscopy (TEM) in a Fe-13%Cr-4%Ni-Mo low carbon martensitic stainless steel It is found that the precipitation of M23C6 carbides along the martensae lath boundaries will result in NI-enrichment in the adjacent region The reversed austenae forms with the NI-enrichment region as the nucleation sites, keeps a cube-cube orientation relationship with the M23C6 carbides and bears the Kurdjumov-Sachs (K-S) relationship with the martensite Moreover, the reversed austenite formed inside the martensae laths is also confirmed. The mechanism for formation of the reversed austenae is discussed in detail (C) 2010 Published by Elsevier BV