Effect of a cyclic hold on the ductility and strength of 45 steel in the complex stressed state at low temperatures

Abstract

1. The effect of preliminary cyclic loading by pulsating tension at room temperature on the low-temperature strength and ductility of steel depends upon the test temperature and the form of stressed state. 2. Preliminary cycling at normal temperature with the maximum stress not exceeding the yield strength by more than 10% has practically no effect on the strength of steel in the +20 to −100°C range. At lower temperatures it reduces the strength properties of the steel, especially in uniform biaxial tension. 3. As a result of cyclic loading, the ductility of steels decreases, and this decrease is more substantial in the direction of preliminary loading. With a decrease in temperature the effect of cyclic loading on the ductility increases.