Effect of simultaneous magnetic field and deep cryogenic heat treatment on the microstructure of 1.2080 tool steel

In this paper, the effect of magnetic field on the structure and hardness of deep cryogenically heat treated 1.2080 tool steel was investigated, via scanning electron microscope (SEM), Rockwell C, and microhardness evaluations. Testing at two different holding durations showed that as a result of the deep cryogenic treatment, the homogeneity of carbides distribution and the carbides percentage in the structure is increased; in contrast, retained austenite vanishes. Furthermore, the results showed that by applying the magnetic filed during the deep cryogenic treatment the start and finish martensite temperatures (M-s and M-f) increase; subsequently, the carbides distribution in the magnetized samples are less homogeneous than that in the non-magnetized samples. Also, in the magnetized deep cryogenically treated samples, the retained austenite completely vanishes; however, the final structure showed a lower carbides percentage compared to the deep cryogenically treated specimens. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.