The Influence of Annealing Temperature on the Strain Rate Sensitivity of Copper in Torsion.

摘要

The effect of annealing temperature on the high strain rate behavior of OFHC copper and a tellurium doped free machining copper is investigated. The annealing temperatures studied include temperatures above and below as well as the recrystalization temperature. The torsional split Hopkinson bar is utilized to achieve shear strain rates up to 2,000/s with a rise time of ten microseconds. The resulting stress-strain curves are compared with those obtained at a strain rate of .0001/s. Specimens of OFHC copper are subjected to incremental strain rate tests so that the change in flow stress corresponding to an increase in strain rate can be evaluated for each specimen. It is concluded that the strain rate sensitivity is positive in nature for each temperature and that its magnitude depends on the annealing temperature. (Author)