Impact behavior of high-strength steel at low temperatures

Abstract

A wide range of material and ballistic tests were conducted to explore the behavior of a high-strength steel at low temperatures. Our test program included quasi-static and dynamic uniaxial and notched tension tests, Charpy V-notch impact tests, and ballistic impact tests. The common understanding is that the ductility of steel decreases dramatically below a certain threshold temperature, which is denoted the ductile-to-brittle transition temperature. In this study, the ductility did not decrease enough to compensate for the increased strength at low temperature. This resulted in an almost unchanged fracture strain in the material tests, a close to linear decrease in absorbed energy in the Charpy V-notch tests, and a higher ballistic limit velocity in the ballistic tests with decreasing temperature.