TEM Study on Relative Orientation Between Adjacent Martensite Laths

The martensite transformation in 1Cr21Ni5Ti duplex stainless steel below 0℃ has been investigated by TEM. The relative orientation between adjacent martensite laths has been measured. The results show that the relative orientation between adjacent martensite laths depends on martensite-austenite orientation relationship. Both K-S relation and N-W relation exists between austenite and martensite. Different variants of lath martensite of K-S relation and(or) N-W relation make relative orientation between adjacent martensite laths complex. Some adjacent martensite laths have a twin relation and there is no retained austenite between them. This twin relation is different from ones between variants of K-S relations. The martensite laths with this twin relation are formed by self-accommodation.