Experimental study of dynamic plasticity at elevated temperatures

In this paper it is shown that the diffraction-grating technique and the optical-displacement technique used by the writer for the study of plastic wave propagation at room temperature, may both be extended to within 100° F of the melting point of aluminum. In addition to the measurement of stress history at the impact face obtained by the extension of the load-bar technique to elevated temperatures, strain-time, surface angle-time, time of contact, coefficient of restitution, and displacement-time behavior at the free end of the struck specimen may all be determined at elevated temperatures. Typical strain-time behavior is shown at 800, 1000, and 1100° F, for three types of impact situations.