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 ...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）.展开更多
为了提高小口径穿甲燃烧弹侵彻陶瓷复合装甲和玻璃复合装甲(透明装甲)的仿真分析精度,本文将传统的FEM(finite element method)-SPH(smooth particle hydrodynamics)耦合计算模型中穿甲燃烧弹弹芯的有限元模型和JC(Johnson-Cook)材料模...为了提高小口径穿甲燃烧弹侵彻陶瓷复合装甲和玻璃复合装甲(透明装甲)的仿真分析精度,本文将传统的FEM(finite element method)-SPH(smooth particle hydrodynamics)耦合计算模型中穿甲燃烧弹弹芯的有限元模型和JC(Johnson-Cook)材料模型分别替换为SPH模型和JH2(Johnson-Holmquist-ceramics)材料模型,提出了新型FEM-SPH耦合计算模型。研究表明,新型FEM-SPH耦合计算模型可以有效模拟弹芯碎裂现象,减少SPH粒子和有限元耦合计算量,进而显著提高仿真模型的计算精度和计算效率,并给出了新型FEM-SPH耦合计算模型的有限元/粒子尺度和建模尺寸的优选结果。展开更多
文摘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）.
文摘为了提高小口径穿甲燃烧弹侵彻陶瓷复合装甲和玻璃复合装甲(透明装甲)的仿真分析精度,本文将传统的FEM(finite element method)-SPH(smooth particle hydrodynamics)耦合计算模型中穿甲燃烧弹弹芯的有限元模型和JC(Johnson-Cook)材料模型分别替换为SPH模型和JH2(Johnson-Holmquist-ceramics)材料模型,提出了新型FEM-SPH耦合计算模型。研究表明,新型FEM-SPH耦合计算模型可以有效模拟弹芯碎裂现象,减少SPH粒子和有限元耦合计算量,进而显著提高仿真模型的计算精度和计算效率,并给出了新型FEM-SPH耦合计算模型的有限元/粒子尺度和建模尺寸的优选结果。
