材料期刊网

利用有限差分方法模拟了Gcr15钢弹丸高速撞击1420铝合金半无限厚靶过程．结果表明：弹丸前方材料向前方运动，而后方材料则经历减速过程甚至出现反向运动，导致自由表面的突起；弹丸前端最大压应力达到1010Pa数量级；应力和应变在弹孔周围的分布极不均匀，越靠近弹孔处越大；随着弹丸的深入，弹丸周围的塑变区加大．

The numerical simulation of 1420 aluminum alloy impacted by hypervelocity steel projectiles waspresented. The maximum stress in the material ahead of the projectile is as high as 1010 Pa since a 3 dimen-sional compression condition is met there. In the region behind the projectile, the material undergoes a decel-eration, and flows towards the surface of the target, resulting in a protuberance at the surface. The stress andstrain in the material are distributed extremely uneven, the closer to the projectile, the greater their intensi-ties. This results in an increase of temperature in material around the projectile, which softens the materialand makes the strain uneven further. At early stage the strain rate in y direction of material near projectile isvery high, resulting in an enlargement of the diameter of the crater. In addition, the deeper the projectile getsinto the target, the bigger is the strain region around the projectile.