冲击加载下FeMnNi合金相变和层裂特性实验研究(英文)

采用激光速度干涉仪(VISAR)、X射线衍射(XRD)和扫描电镜(SEM)联合测试技术,利用等厚对称加载和逆向加载实验,研究了Fe MnNi合金的冲击相变和层裂行为。结果发现:加载压力大于6.5 GPa时,Fe MnNi合金样品发生α→ε相变;中心稀疏波的卸载作用使内压力降至4~5 GPa时,Fe MnNi合金样品发生ε→α逆相变,并伴有卸载稀疏冲击波形成。分析Fe MnNi合金样品中塑性波、相变波、稀疏波和稀疏冲击波的传播作用过程,发现加载压力大于其相变应力时,等厚对称加载下Fe MnNi合金存在产生层裂行为的物理机制。

Experimental Study on Phase Transition and Spall Fracture in FeMnNi Alloy under Shock Pressure

By means of velocity interferometer system for any reflector (VISAR) ,X-ray diffraction (XRD) and scanning electron microscope (SEM), phase transition and spalling behavior of the FeMnNi alloy were studied through symmetric impact and reverse impact experiments. The FeMnNi alloy experiences a α→ε phase transformation when shocked to the pressure above 6. 5 GPa. The FeMnNi alloy produces ε→α reverse phase transition and rarefaction shock wave when the pressure reduce to 4～5 GPa due to the rarefaction wave. By analyzing the interaction among plastic wave, phase transition wave, rarefaction wave and rarefaction shock wave.it was found that the FeMnNi alloy has a physical mechanism inducing the formation of spall behavior in symmetric impact experiments as the impact stress exceeds α→ε transition threshold.