Stress-assisted and strain-induced martensite morphologies in an Fe--21Ni--0. 6C alloy

Journal Article · Sat Jan 01 04:00:00 EST 1977 · Metallography; (United States)

DOI:https://doi.org/10.1016/0026-0800(77)90033-7· OSTI ID:5006328

Snell, E O; Shyne, J C; Goldberg, A

Morphologies resulting from the transformation of austenite to martensite during deformation of an Fe-21Ni-0.6C alloy are described. Samples were deformed either by conventional quasistatic tension loading, by high-strain-rate inertial tension loading, or by flyer-plate, compression shock loading. The various martensites observed are classified either as stress-assisted or strain-induced martensite. The stress-assisted martensite is characteristic of the plate martensite formed by lowering the temperature below the M/sub 8/ of the alloy. The strain-induced martensite, which forms only during plastic deformation, appears as laths or platelets, but with different morphologies in the tension-loaded and shock-loaded samples. In the tension-loaded, deformed samples, the laths are clustered within the deformation bands. In the shock-loaded samples, arrays of relatively thin, long laths, where observed, aligned parallel to the (111)/sub gamma/ twin boundaries of the more homogeneously deformed parent austenite. Where both martensites are present, the strain-induced martensite appears to have formed prior to the stress-assisted martensite. Differences in morphology between the shock-loaded and nonshock-loaded samples are ascribed to differences in the extent of dislocation generation and movement.

• Research Organization: Univ. of California, Livermore
• OSTI ID: 5006328
• Journal Information: Metallography; (United States), Journal Name: Metallography; (United States) Vol. 10; ISSN MEIJA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
CARBON ADDITIONS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DEFORMATION
IRON ALLOYS
IRON BASE ALLOYS
MICROSTRUCTURE
MORPHOLOGY
NICKEL ALLOYS
NICKEL STEELS
PHASE TRANSFORMATIONS
STEELS
STRAINS