Abstract
The substructures of two Fe-Ni-C alloys that form platelike martensite have been studied by transmission electron microscopy (TEM). Planar features with a {011 } habit are observed, in addition to the usual {112 } transformation twins and arrays of screw dislocations. The results of diffraction-contrast experiments are consistent with these {011 } defects being fine twins within which the carbon atoms occupy a different octahedral interstitial sublattice from the surrounding matrix. In any given martensitic plate, this twinning appears to occur preferentially on the {011 } plane containing the same {111 } direction as the operative {112 } transformation-twinning variant. The possibility that {011 } twinning occurs during the martensitic transformation and/or when virgin martensite is heated from subambient temperatures is discussed in relation to crystallographic observables such as the martensitic habit plane and axial ratios.
Original language | English (US) |
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Pages (from-to) | 2739-2747 |
Number of pages | 9 |
Journal | Metallurgical Transactions A |
Volume | 20 |
Issue number | 12 |
DOIs | |
State | Published - Dec 1 1989 |
ASJC Scopus subject areas
- Engineering(all)