不同组织状态TC4合金靶材损伤行为的研究

采用直径为4mm的CoCr15钢珠作为弹丸对两种不同组织状态的TCA合金进行撞击试验，撞击速度为1．5km／s；观察撞击后不同厚度靶材的宏观损伤及微观损伤行为。结果表明：靶材的组织状态对靶材的宏观损伤行为有很大的影响；时效处理态的组织具有更高的绝热剪切敏感性，在中厚靶发生了绝热冲塞；退火态中厚靶的背面则发生了凸起。各种靶材的微观损伤形式基本相同，在弹坑附近出现了大量的绝热剪切带；微孔洞在绝热剪切带内形核、长大并连结成为裂纹。

Study of Damage Behavior of Different Microstructure TC4 Alloy Targets

The targets of TC4 alloy with two different microstructures are impacted by 4 m m d iameter GCr15 steel ball with a speed of 1.5 km/s. The damage behavior of diffe rent thickness targets as well as micro damage behavior are observed. Experimental results show that the alloy microstruc ture has obvious effect on the macro-damage. The microstructure of aged state h as more adiabatic shear susceptibility and adiabati c plugging forms in the mid-thickness target. A bulge is observed on the back o f mid-thickness target of annealed state. Different targets have always the sa me micro-da mage forms. Abundant adiabatic shear bands (ASBs) are observed near craters. The micro-voids nucleate, grow and coarsen in ASBs, which lead to premature failur e.