Accession Number : AD0730137

Title :   The Effect of Prior Deformation on the Strength and Annealing of Reverted Austenite.

Descriptive Note : Technical rept.,

Corporate Author : PHILCO-FORD CORP NEWPORT BEACH CALIF AERONUTRONIC DIV

Personal Author(s) : Koppenaal,Theodore J. ; Gold,Edward

Report Date : 17 SEP 1971

Pagination or Media Count : 32

Abstract : The strength, annealing behavior, and microstructure of reverted austenite has been measured in an FE-31%Ni-.03%C alloy that was plastically deformed prior to the reversion to austenite. Mechanical properties of reverted austenite (e.g., austenite formed by the reverse martensite shear transformation) were measured as a function of the amount of prior deformation, heating and cooling rates to the reversion temperature, austenitizing temperature and time, repetitive cycling from martensite to reverted austenite, and pre-reversion heat treatments. The results showed that 80% prior deformation increases the yield strength of reverted austenite about 30%. Along with this strengthening, the dislocation configuration changes from a random array of tangled dislocations in reverted samples without prior deformation to a subgrain structure with a high density of tangled dislocations within the subgrains in samples with 80% deformation prior to reversion. Although smaller amounts of prior deformation (20%) have only a small effect on the strength of the reverted austenite, this amount of prior deformation significantly increases the driving force for recrystallization. The results are explained on the basis that the prior deformation and the reversion process produce separate components to the strength and annealing behavior. (Author)

Descriptors :   (*AUSTENITE, DEFORMATION), PHASE STUDIES, NICKEL ALLOYS, HARDENING, MICROSTRUCTURE, TENSILE PROPERTIES, ANNEALING

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE