Mechanical stability of retained austenite in tempered 9Ni steel |
| |
Authors: | C K Syn B Fultz J W Morris |
| |
Affiliation: | (1) Department of Materials Science and Engineering ahd the Materials and Molecular Research Division, Lawrence Berkeley Laboratory, University of California, 94720 Berkeley, CA |
| |
Abstract: | The behavior of the thermally stable austenite in the ductile fracture surface layer of a grain-refined and tempered 9Ni steel broken at 77 K was studied through use of Möss-bauer spectroscopy and transmission electron microscopy. Thin foils revealing the mi-crostructural profile of the fracture surface layer were prepared by electroplating a thick pure iron layer on the fresh fracture surface, then thinning a profile sample through a combination of conventional twin-jet electropolishing and ion milling techniques. The re-sults of both Mössbauer spectroscopy and TEM studies showed that the thermally stable austenite transforms to a dislocated martensite in the deformed zone adjacent to the duc-tile fracture surface. This result suggests that transformation of the retained austenite present in tempered 9Ni steel is compatible with low temperature toughness, at least when the transformation product is a ductile martensite. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|