摘要
为了认识爆炸焊接驻点近区材料的力学和热学行为 ,分析波状界面和绝热剪切带生成 ,采用理想流体对称碰撞模型沿流线研究了驻点近区的应变率分布规律 ,并推导出了驻点应变率的理论计算公式。通过数值与理论计算对爆炸焊接碰撞角、界面距离等因素对应变率的影响进行了讨论。计算结果表明 ,爆炸焊接中强烈变形集中在驻点附近区域 ,其应变率高达 10 6～ 10 7s-1,拉压应变率的绝对值在驻点处达到最大 ;而剪应变在焊接界面上为零 ,其最大值出现在驻点的前方 ,为拉压应变率的约二倍。
It is important to analyze the distribution of strain rate near the stagnation point for understanding the mechanics and thermal behaviors of the material during explosive welding. It is also useful for analyzing formation of interface waves and the adiabatic shear bands(ASB). In this paper, an ideal fluid model of symmetrically colliding is taken to analyze the distribution rule of strain rate on streamlines, and a theoretical formula of strain rate is also deduced. According to theoretical and numerical calculation, the influences of oblique colliding angle and interface distance on the strain rate are also discussed. The results show that the deformation caused by explosive welding are quite centralized nearby the stagnation point and the strain rates of the stagnation point can approach to 106-107s-1. The absolute value of tensile and compression strain rate get to their maximum at the stagnation point, but there is no shear strain at explosive welding interface, the maximum of shear strain appears in front of stagnation point and approaches to be two times of tensile and compression strain rate.
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2002年第4期315-320,共6页
Explosion and Shock Waves
基金
国家自然科学基金项目 (19972 0 1510 172 0 2 5 )
辽宁省自然科学基金项目
关键词
分布规律
爆炸焊接
驻点
应变率
Deformation
Numerical analysis
Shear stress
Strain rate
Tensile stress
