Strain Rate Effects and Temperature History Effects for Three Different Tempers of 4340 VAR Steel

Abstract
A series of experiments is described in which specimens of AISI 4340 VAR steel are deformed in shear at temperatures ranging from -190C to 20C. The tests were performed in a torsional Kolsky bar at quasi-static and dynamic strain rates. Before testing all the specimens were normalized, austenitized and tempered either at 200 C, 425 C or 600 C, representing hardnesses of 55, 44, and 33, respectively, on the Rockwell C scale. In addition to constant temperature and constant strain rate tests, a number of experiments was performed to study history effects in these tempers. For this purpose a prestrain was imposed at one temperature and strain rate, followed by continued straining at a new temperature or at a new strain rate.

This publication has 0 references indexed in Scilit: