TC21钛合金锻件淬火过程温度场及热应力场数值模拟

Numerical Simulation of Temperature Field and Thermal Stress Field

摘要:

通过利用ANSYS有限元分析软件对TC21钛合金锻件淬火过程进行数值模拟，获得TC21钛合金锻件淬火不同时刻温度场分布及热应力场分布，以及锻件上所选节点温度、热应力随淬火时间的变化关系，并观察从锻件心部至边部的组织变化，研究冷却速率对组织变化的影响规律。结果表明，当淬火3600 s时，锻件表面已冷却至室温，而心部仍然保持较高温度；从锻件心部至表面冷却速度逐渐增加，并且越靠近表面，组织越细小。 淬火开始阶段，锻件各点热应力迅速升至最大值，随着淬火时间延长，锻件表面及心部热应力均逐渐减小，至淬火结束时，锻件最大残余应力仅为77 MPa。

Abstract:

The quenching process of TC21 titanium alloy forging was simulated by ANSYS finite element analysis software, and the temperature field and the thermal stress field of TC21 titanium alloy forging at different quenching time were obtained, as well as the relationship between the temperature and stress of selected nodes and quenching time. Moreover, the change of microstructure from the forging center to the edge was observed in order to study the effect of cooling rate on the microstructure change. The results show that when the quenching time reaches to 3600 s, the forging surface has cooled to room temperature, while the forging center still maintains a high temperature; the cooling rate increases continually from the forging center to the surface, and the microstructure becomes much finer with the distance from the surface decreasing. At the beginning of quenching, the thermal stress of all parts of the forging rises to the peak rapidly, and then the thermal stress of the surface and the center decrease gradually with the quenching time increasing. The maximum residual stress is only 77 MPa at the end of quenching.