Shock response of stainless steel at high temperature

Abstract

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–1000 K at shock stress of 8 GPa, the corresponding spall strength σ_f and Hugoniot elastic limit σ_HEL are determined from the wave profiles. In the temperature range of 300 K–806 K, σ_f and σ_HEL decrease linearly with increasing temperature T, i.e., σ_f = 5.63-4.32 × 10⁻³T, σ_HEL = 2.08-1.54 × 10⁻³T, but when heated to 980 K, σ_HEL increases from 0.84 GPa at 806 K to 0.93 GPa at 980 K and σ_f keeps at an almost fixed value of 2.15 GPa. The TEM analysis on recovery samples identified 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. While no such products were found in the samples of 300 K and 650 K.