绝热剪切效应对背水靶板的抗侵彻特性影响的研究

绝热剪切效应是材料破坏的重要机理之一.文章开展了动态冲击作用下的材料绝热剪切试验,计算了绝热条件下材料的塑性温度升高.建立了背水靶板的FEM全流固耦合模型,采用考虑了温度效应的Johnson-cook模型开展了爆炸破片侵彻舰船液舱舱壁过程的计算.结果表明:(1)材料在高应变率下的绝热温升不可忽略;(2)弹体侵彻背水靶板过程可分为4个典型阶段,分别为墩粗凿坑阶段、碰撞形成速度共同体阶段、绝热剪切阶段和扰动液体阶段;(3)考虑温度效应的剩余速度明显小于不考虑温度效应的剩余速度;速度较低时,是否考虑温度效应预测的剩余速度值差异较小,随着初始速度的增大,差异逐渐增大.

Effect of Adiabatic Shear on Penetration Properties of Water-back Plate

Adiabatic shear is one of the complicated damage mechanics of materials. In high strain rate situation, plastic deformation will bring temperature increasing, which makes the damage of the target plate is penetrated and melted. In this paper, adiabatic shear tests were designed, and a finite element model (FEM) based on Johnson-Cook method was set up, the experimental and numerical results were verified and compared to each other. Based on the FEM, the process of projectile pene-trating water-back plate was analyzed, results indicated that: (1) In high strain rate loading, the temperature effect caused by adiabatic shear must be figured out;(2) The process of projectile pen-etrating liquid-filled tank can be divided into four distinct stages: mushrooming propagating, crush-ing, shearing and perturbing; (3) The residual velocity of the fragments considering adiabatic shear effect is smaller than that of without considering the effect. And the difference value is small when the initial velocity is slow, but will increase with the increasing of the initial velocity.