摘要
Al-Sc and Al-Ti semi-infinite targets were impacted by high-speed projectiles at velocities of 0.8, 1.0, 1.2 and 1.5 km/s, respectively. It is found that the Al-Sc targets demonstrate more excellent ability to resist high-speed impact. It is concluded that different microstructures of Al-Sc and Al-Ti alloys, including different grain sizes and secondary particles precipitated in the matrix, result in their greatly different capabilities of resisting impact. Furthermore, the effect of the size range ofnanoscale A13Sc precipitate in A1-Sc alloy on the resistance of high-speed impact was investigated. In addition, computer simulations and validation of these simulations were developed which fairly accurately represented residual crater shapes/geometries. Validated computer simulations allowed representative extrapolations of impact craters well beyond the laboratory where melt and solidification occurred at the crater wall, especially for hypervelocity impact (〉5 km/s).
研究Al-Sc和Al-Ti半无限靶材在高速弹体撞击下的动力学响应,弹体的撞击速度分别为0.8、1.0、1.2和1.5 km/s。结果表明:Al-Sc靶材具有更优异的抗高速撞击能力。研究发现,不同的显微组织结构,包括晶粒大小、基体中析出的沉淀相粒子,导致Al-Sc和Al-Ti合金具有不同的抗撞击能力。同时,讨论Al-Sc合金中的纳米级Al3Sc粒子的尺寸效应对抗撞击能力的影响。此外,通过数值模拟对高速撞击后弹坑形状/几何尺寸进行仿真,并与实验结果进行对比验证。仿真分析结果较准确地复现了实验结果,在此基础上通过外推的方法将弹体速度推广到超高速范畴(>5 km/s)进行分析。在超高速撞击作用下,弹坑表面发生熔化和凝固现象。