摘要
为研究金属粘性效应时的搅拌摩擦焊接材料流动行为,采用率相关本构描述搅拌摩擦焊接过程中的材料行为,并与非率相关材料模型的计算结果进行了对比.结果显示,由于考虑了金属的粘性效应.用率相关材料模型模拟搅拌摩擦焊接过程能更好地反映材料流动行为的本质.在搅拌摩擦焊接中,材料沿搅拌头切向方向的运动构成了搅拌摩擦焊接构件材料流动的主要形式.焊接构件-搅拌头接触面上的接触压力在搅拌头前方较大,在搅拌头后方较小,这一规律在率相关模型中更为明显.搅拌头前方材料在搅拌头的挤压之下向远离搅拌头的方向运动,而搅拌头后方的材料要填充由于搅拌头的移动而留下的空间,这一过程是保证搅拌摩擦焊接顺利完成的一个主要因素.因此,用率相关模型模拟搅拌摩擦焊接过程中的材料力学行为更为接近真实情况.
To study the material behaviors in friction stir welding in consideration of viscosity effects,the rate dependent constitutive model was adopted to describe the material behaviors in friction stir welding and the corresponding caculation results were compared with those of the rate independent material model. Results indicate that the simulation of the friction stir welding process by using the rate dependent material model is much more similar to the real manufacture. The tangent movement of the material takes the main contributions in friction stir welding. The contact pressure in front of the pin is much higher than that behind the pin, which can be seen more clearly in the rate dependent material model. Due to the extrusion of the pin, the material in front of the pin moves away from the pin, however, the material behind the pin fills the vacant place formed by the movement of the pin. It is a main factor to perform the friction stir welding process successfully. The predicted material behaviors are closer to those of the real material flow in friction stir welding when the rate dependent model is used.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2008年第5期696-701,共6页
Materials Science and Technology
基金
周家自然科学基金资助项目(10225212
10802017)
长江学者和创新团队发展计划
国家基础性发展规划资助项目(2005CB321704)
关键词
搅拌摩擦焊接
材料流动
率相关
应变率
friction stir welding
material flow
rate dependent
strain rate
