Accession Number : AD0622543

Title :   SUBSTRUCTURE AND MECHANICAL PROPERTIES OF A DRAWN AND ANNEALED IRON-SILICON ALLOY,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF METALLURGY AND MATERIALS SCIENCE

Personal Author(s) : Comerford,M. F. ; Thomas,D. A.

Report Date : 06 FEB 1964

Pagination or Media Count : 8

Abstract : Polycrystalline wires of Fe-3.2 wt pct Si were colddrawn to 31, 66, and 87 pct reductions of area. Mechanical properties and microstructures were studied after recovery and recrystallization. An initial increase in strength during recovery was ascribed to strain aging, and subsequent softening was largely due to polygonization rather than recrystallization. No unique activation energies could be determined for the recovery process. Rather, activation energies ranged from 60,600 cal per mole at 10 pct recovery to 83,200 cal per mole when recovery was 50 pct complete. Sites for the nucleation of recrystallization were found to depend on time and temperature. In the early stages of recrystallization, nucleation occurred in deformation bands. Later, or at high temperatures, recrystallized grains were nucleated primarily at grain boundaries. Polygonized structures did not seem to be preferred sites for nucleation. (Author)

Descriptors :   (*IRON ALLOYS, SILICON ALLOYS), MECHANICAL PROPERTIES, DRAWING(FORMING), HEAT TREATMENT, NUCLEATION, GRAIN BOUNDARIES, HARDNESS, RECRYSTALLIZATION, HEAT OF REACTION, TENSILE PROPERTIES, METALLOGRAPHY, DEFORMATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE