Shock response of stainless steel at high temperature

Measurements of the dynamic tensile strength of HR-2 (Cr-Ni-Mn-N) stainless steel have been carried out over the initial temperature range of 300 K-10 00 K at shock stress of 8 GPa, the corresponding spall strength sigma(f) an d Hugoniot elastic limit sigma(HEL) are determined from the wave profiles. In the temperature range of 300 K-806 K, sigma(f) and sigma(HEL) decrease l inearly with increasing temperature T, i.e., sigma(f) = 5.63-4.32 x 10(-3)T , sigma(HEL) = 2.08-1.54 x 10(-3)T, but when heated to 980 K, sigma(HEL) in creases from 0.84 GPa at 806 K to 0.93 GPa at 980 K and sigma(f) keeps at a n almost fixed value of 2.15 GPa. The TEM analysis on recovery samples iden tified the existence of intermatallic compound Ni3Al and the carbide Cr23C6 in the sample of 806 K, another intermatallic compound Ni3Ti was found in the sample of 980 K. All these products emerge along crystal boundary. Whil e no such products were found in the samples of 300 K and 650 K. (C) 2000 K luwer Academic Publishers.