SANS study of the microstructural evolution of martensitic steels under thermal ageing and neutron irradiation

SANS technique has been used to study the microstructural evolution of mart ensitic steels containing 7-12% Cr, under thermal ageing and neutron irradi ation. Some of the investigated alloys are industrial low activation marten sitic (LAM) materials, where alloying elements have been substituted by ele ments with low radiological impact. For materials quenched from the austeni tic phase, a direct correlation was found between the hardening and the num ber density of M2C precipitates induced by thermal ageing at 500 degrees C. Irradiation-accelerated spinodal decomposition of the B.C.C. ferrite was o bserved in alloys containing large (=11%) chromium content. (C) 2000 Elsevi er Science B.V. All rights reserved.