TA18钛合金管材多行程皮尔格冷轧过程三维有限元模拟：I 理论解析、模型建立与验证

皮尔格冷轧技术制备的TA18钛合金管材具有高比强度、冷加工性能好、织构分布合理等优异的综合性能,在飞机和航天器液压管路系统、石油勘探钻杆中得到了广泛的应用。根据多行程皮尔格冷轧过程力学分析,获得了成形过程的精确运动模式和管材应力状态。然后,基于有限元软件ABAQUS/Explicit,建立了TA18钛合金管材多行程皮尔格冷轧三维有限元模型,并解决了建模关键技术,包括:虚拟曲柄连杆机构实现方法、多行程周期式运动控制方法、复杂模具几何实体定义、滚动与滑动摩擦定义。利用能量守恒原理和实验验证了模型的可靠性,以及利用成形过程等效应力和等效塑性应变分布评估了模型。

Three-Dimensional FE Simulation of Multi-strokes Cold Pilgering of TA18 Titanium Alloy Tube: I Theoretical Analysis, Modeling and Validation

TA18 titanium alloy tubes based on cold pilgering are widely used for the hydraulic system of airplanes and spacecrafts and drill pipes of oil exploration due to their high specific strength, good cold processability and reasonable texture distribution. In this study, according to the mechanical analysis of multi-strokes cold pilgering process, precision motion mode and stress state of the tube during the forming process were obtained. Furthermore, a three-dimensional FE model of multi-strokes cold pilgering of TA18 titanium alloy tube was developed in the FE software environment of ABAQUS/Explicit. Some key modeling techniques were proposed, including the implementation of virtual crank-connecting-link device, the control method of multi-strokes motion modes, the definition of complex geometric formation and the definition of rolling friction and sliding friction. The FE model was validated by energy conservation principle and experimental results, and evaluated by the distributions of equivalent stress and equivalent plastic strain during the forming process.