REDISTRIBUTION OF INTERSTITIAL ATOMS AND AGING OF FE-N ALPHA' MARTENSITE

Different experimental measurements show that transformations of marte nsite occur from very low temperature, often below 77K. In order to un derstand the redistribution of interstitial atoms which is studied by Mossbauer spectroscopy near room temperature the previous low temperat ure changes are briefly discussed. The Mossbauer data related to cubic gamma, gamma', alpha' and alpha'' Fe-N alloys are presented. It is sh own that the interstitial atom distribution and redistribution of inte rstitial atoms is partially inherited from austenite and that gamma' F e4N nuclei corresponds in gamma and alpha' to N-Fe-N chains oriented a long <001> in gamma and along <110> in alpha'.