(1. 合肥工业大学 材料科学与工程学院，合肥 230009;
2. 上海大众汽车有限公司宁波分公司，宁波 315000)
摘 要: 对在不同参数下热变形后水冷的TA15合金进行800 ℃保温1 h的真空退火热处理，借助于电子背散射衍射(EBSD)技术，分析热变形参数对TA15合金退火显微组织的影响。针对TA15合金热加工工艺参数与显微组织特征参数之间高度复杂的非线性关系，提出利用响应面法建立二者之间的量化模型，给出表征工艺参数与显微组织特征参数之间的响应面函数。同时，对响应面模型进行多目标可视化优化，获得最优工艺参数范围:变形温度为950 ℃，应变速率为0.063~0.1 s-1，变形量为0.4~0.6时可以获得具有优异综合力学性能的三态组织;变形温度为1000 ℃，应变速率为0.1~0.316 s-1，变形量为0.2~0.45时可以获得具有高损伤容限性的片层组织。
关键字: TA15合金;退火热处理;响应面法;优化;三态组织
（1. School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China;
2. Ningbo Branch, Shanghai Volkswagen Automotive Corporation Ltd., Ningbo 315000, China）
Abstract:TA15 titanium alloy deformed at different parameters was conducted heat treatment at 800 ℃ and kept for 1 h, and at the same time the electron backscattered diffraction (EBSD) technique was applied to analyze the influence of thermal deformation parameters on the microstructure of annealed TA15 titanium alloy. As the result that the highly complex nonlinear relationship between process parameters and microstructure parameters of TA15 titanium alloy, a quantitative prediction model was built based on the response surface methodology (RSM), the response surface function representation of process parameters and microstructure characteristic parameters were obtained. In addition, the optimal process parameters were obtained by multi-objective visualization optimization. The results show that it can be obtained tri-modal microstructure with excellent mechanical properties at 950 ℃, strain rates of 0.063-0.1 s-1, the amount of deformation of 0.4-0.6. However, it can be obtained lamellar structure with high damage tolerance at 1000 ℃, strain rates of 0.1-0.316 s-1, the amount of deformation of 0.2-0.45.
Key words: TA15 titanium alloy; heat treatment; RSM; optimization; tri-modal microstructure
