The Strength of Martensite
Abstract
Fe-Ni-C alloys were selected to determine the role of C in the strengthening of virgin (untempered) martensite. Martensites formed at subzero temperatures were maintained at low-temperature levels for the studies. The axial ratio of the tetragonal lattice increased with the C concentration, but there was an extra tetragonality independent of C and which is thought to result from the presence of stacking faults. The extra tetragonality disappeared on aging above room temperature where the regular tempering reactions occur. The C-dependent strengthening of virgin martensite can be described as a solid-solution hardening phenomenon. The fine structure of the martensite is thought to be a contributory factor in the over-all strengthening. In addition, at temperatures above about -60 deg C, age hardening due to carbide precipitation provides a further component of strengthening which increases with the carbon content; this increment is relatively small compared to the solid-solution effect.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1962
- Accession Number
- AD0281894
Entities
People
- Morris B Cohen
- P. G. Winchell
Organizations
- Massachusetts Institute of Technology