Thermal expansion and phase transformations of nitrogen-expanded austenite studied with in situ synchrotron X-ray diffraction

Thermal expansion and decomposition of nitrogen-expanded austenite has been studied with in situ synchrotron X-ray diffraction. A transitional phase with composition M₄N (M = Fe, Cr, Ni, Mo) appears for high nitrogen contents and the decomposition products are austenite, ferrite and CrN.