Non-cube-on-cube orientation relationship between M23C6 and austenite in an austenitic stainless steel

Crystallographic orientation relationship between M23C6 carbides and austenite in the lightweight high carbon stainless steel Fe- 17Cr- 9Ni- 6Mn-4Al- 0.42C (wt.%) was investigated by diffraction analysis in scanning and transmission electron microscopes. Electron backscatter diffraction analysis in SEM indicated the existence of an orientation relationship approximated by the Kurdjumov-Sachs (K-S) orientation relationship between the M23C6 carbides induced by aging and the austenitic matrix. The observation of an orientation relationship deviating from the commonly reported cube-on-cube orientation relationship was explained by the formation of M23C6 carbides via M7C3 carbides as an intermediate phase.

Automated summary

This study investigated the crystallographic orientation relationship between M23C6 carbides and austenite in lightweight high carbon stainless steel. The findings showed an orientation relationship approximated by the Kurdjumov-Sachs (K-S) orientation relationship between the carbides and the austenitic matrix, deviating from the commonly reported cube-on-cube orientation relationship, which could be explained by the formation of M23C6 carbides via M7C3 carbides as an intermediate phase.