Lath martensites in carbon steels - are they bainitic
A detailed metallographic, crystallographic, and spectroscopic analysis of lath martensites formed by quenching low and medium carbon steels confirms an earlier suggestion that these structures are not strictly martensitic since carbon redistribution occurs during transformation. Perhaps a better description would be untransformed upper bainite with the interlath phase being carbon enriched austenite rather than carbide, as occurs in classic upper bainite. A summary of new crystallogrpahic results using convergent beam electron diffraction is presented. In a given packet, the laths cluster around <111>/sub ..cap alpha..'/, and <100>/sub ..cap alpha..'/, but as reported earlier, other orientations also occur between them. The common axis between a particular bundle of laths is <110>/sub ..cap alpha..'/. Rotations between bundles of laths and deformation of retained austenite may be important in minimizing the shape deformation.
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 7045412
- Report Number(s):
- LBL-13098; ON: DE83000302
- Country of Publication:
- United States
- Language:
- English
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