Effects of Strain Rate and Temperature on the Mechanical Properties of 10NiCrMo Hull Steel

Effects of high strain rate and low temperature on tensile properties of 10NiCrMo hull steel were investigated.The results of tensile test showed that high strain rate and low temperature had effects on mechanical properties of 10NiCrMo hull steel.At room temperature and lower strain rates (1.6×10^-3/s~1.6×10^-1/s), with increasing the strain rate, the tensile strength and plasticity of the steel had no obvious change.At higher strain rates (2.8×10²/s~1.2×10³/s), with increasing the strain rate, the tensile strength and plasticity increased slightly and embrittlement did not occur.At normal strain rate and from room temperature to -196 ℃, the tensile strength R_m of the steel increased with decreasing temperature, the increment of the tensile strength reached 30% at -196 ℃;and the elongation increased as well with decreasing temperature, the increment of the elongation was about 14% at -196 ℃.Not only there was no embrittlement of the steel at low temperature, but also the plasticity was better than that at room temperature.But with the coaction of high strain rate and low temperature, the tensile strength increased and the plasticity decreased (about 50%) obviously in comparison with the results of common tensile test.The unique mechanical properties of 10NiCrMo hull steel at high strain rates or low temperatures were related to its uniformed deformation capacity and the change of fracture mechanism, and there was no corresponding relationship between the plasticity and the fracture mode.