Large strain extrusion machining (LSEM) is a typical process for preparing ultrafine or nanocrystalline strips. It is based on large plastic deformation. The processing parameters of LSEM in this study were optimized by experiments and simulations. Using the orthogonal array, signal-to-noise ratio, and analysis of variance, the influence and contribution of processing parameters on response variables were analyzed. Because of the difference in processing parameters between optimizing the average grain size and the maximum temperature, the response variables analyzed must be correctly selected. Furthermore, the optimal processing parameters for obtaining the minimum average grain size and the lowest maximum temperature are analyzed. The results show that the tool rake angle is the most important factor. However, the level of this factor required to achieve the minimum average grain size is different from that required to obtain the lowest maximum temperature. The validity of the method is verified through experiments and simulations.

大应变挤压加工（LSEM）是制备超细或纳米晶条的典型方法。它基于较大的塑性变形。通过实验和仿真优化了本研究中LSEM的加工参数。使用正交阵列，信噪比和方差分析，分析了处理参数对响应变量的影响和贡献。由于优化平均晶粒尺寸和最高温度之间的加工参数不同，必须正确选择分析的响应变量。此外，分析了用于获得最小平均晶粒尺寸和最小最高温度的最佳加工参数。结果表明，刀具前角是最重要的因素。然而，实现最小平均晶粒尺寸所需的该因子的水平不同于获得最低最高温度所需的该因子的水平。通过实验和仿真验证了该方法的有效性。