大型TA19钛合金棒材形变及相变织构模拟  

Simulation of Deformation and Transformation Texture of Large TA19 Titanium Alloy Bar

作　　者：李志尚 熊智豪 杨平[1] 顾新福 颜孟奇 沙爱学 Li Zhishang;Xiong Zhihao;Yang Ping;Gu Xinfu;Yan Mengqi;Sha Aixue(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]北京科技大学材料学院,北京100083 [2]北京航空材料研究院,北京100095

出　　处：《稀有金属材料与工程》2022年第10期3785-3792,共8页Rare Metal Materials and Engineering

基　　金：国家军品配套科技项目(JPPT-135-GH-2-017)。

摘　　要：密排六方结构相具有显著的各向异性特征,室温时TA19钛合金棒材中一次α相含量占70%以上,因此α相织构对TA19钛合金棒材力学性能的好坏起主要作用,有效的织构预测能够大大地降低生产成本,提高生产效率;也能帮助确定织构形成机制。本研究采用宏观有限元模型和介观粘塑性自洽模型(VPSC)多尺度耦合的方法,并考虑β→α相变过程,模拟了大型TA19钛合金棒材接近实际工艺条件下的锻造过程。首先模拟得到了相变点以上棒材心部、R/2和边部的β相形变织构;然后通过分析不同位置的β相织构特征,根据Burgers取向关系得到了棒材冷却过程中发生β→α相变时不同的变体选择规律,得到α相相变织构;最后结合相变后棒材心部、R/2和边部的α相织构特征,分析了不同初始取向的α晶粒在不同滑移系开动时的取向变化,并模拟得到了最终的α相形变织构。通过最终模拟结果与实际锻造结果对比,发现两者吻合良好。说明本模型对钛合金棒材锻造过程中形变及相变织构的预测具有良好的可靠性,这对钛合金锻造棒材中织构的控制与调整具有重要意义。The hexagonal phase with close packed structure has a obvious anisotropic characteristic,and the primaryαphase content in TA19 titanium alloy bar at room temperature is as high as 70%.Therefore,theαtexture has a significant effect on the mechanical properties of TA19 titanium alloy bar,and effective texture prediction can greatly reduce the production cost and improve the production efficiency,and it can also help to determine the mechanism of texture formation.In this study,the multi-scale coupling method of macroscopic finite element model and mesoscopic visco-plastic self consistent model was used to simulate the forging process of large TA19 titanium alloy bar under close to the actual process conditions,and theβ→αphase transition process was considered.At first,the simulatedβdeformation textures of the center,R/2 and edge of the bar above the phase transition temperature are obtained.And then,according to the Burgers orientation relationship,the laws of variant selection of different positions of bar during cooling are obtained by analyzing theβtexture characteristics of different positions,and theαtransformation textures are obtained.Finally,combining with theαtexture characteristics at the center,R/2 and edge of the bar after transformation,the orientation evolution ofαgrains with different initial orientations was analyzed when different slip systems started,andαdeformation textures are obtained.By comparing the final simulation results with the actual forging results,it is found that they are in good agreement.It illustrates that the model has good reliability in predicting the deformation and transformation textures of titanium alloy bars during forging,which has great significance for controlling and adjusting the texture of titanium alloy bars during forging.

关 键 词：钛合金 形变 相变 织构 模拟 

分 类 号：TG146.23[一般工业技术—材料科学与工程]