(1. 西北工业大学 凝固技术国家重点实验室，材料学院，西安 710072；
2. 西安重型机械研究院有限责任公司，西安 710032)
摘 要: 研究确定难变形Inconel 625合金大型厚壁管挤压加工窗口，是获得具有良好组织性能挤压管材的关键。采用响应面法建立了一种确定基于温控挤压加工窗口的方法。首先，采用基于有限元计算数据的正交回归方法，建立了分别描述温升和峰值温度与关键挤压参数之间的响应面模型；其次，基于建立的响应面模型，分析揭示了关键挤压参数对温升和温度峰值的交互作用规律；最后，通过绘制挤压速度和初始温度空间峰值温度的等高线图，建立了不同挤压比下挤压加工窗口。基于该挤压加工窗口，可方便快速地确定合适的关键挤压参数组合。
关键字: 型材挤压；加工窗口；响应面法；难变形材料；有限元模拟
（1. State Key Laboratory of Solidification Processing, School of Materials Sciences and Engineering,
Northwestern Polytechnical University, Xi’an 710072, China;
2. China National Heavy Machinery Research Institute Co., Ltd., Xi’an 710032, China）
Abstract:Identifying suitable processing window is necessary but difficult for achieving favorable microstructure and performance in extrusion of large thick-walled pipe with difficult-to-deform Inconel 625 alloy. In this work, a method was established for identifying the extrusion process window considering temperature control using response surface methodology. Firstly, the response surface models, which correlate temperature rise and peak temperature to key extrusion parameters, have been developed by orthogonal regression based on finite element calculated data. Secondly, the coupled effects of the key extrusion parameters on the temperature rise and peak temperature have been disclosed based on the regression models. Lastly, suitable extrusion processing windows, which are described by contour map of peak temperature in the space of extrusion speed and initial billet temperature, have been established for different extrusion ratios. Using the identified process window, a suitable combination of the key extrusion parameters can be determined conveniently and quickly.
Key words: profile extrusion; processing window; response surface methodology; difficult-to-deform materials; finite element simulation
