高速切削因众多优点被广泛研究，然而切削速度快这一特点也限制了对切削过程的认识。为了研究切削过程各类物理参量的变化规律，进而应用到工程实际，提出了从流动的角度去认识切削过程的思路。分析了从材料流动观点研究应变率的依据，提出了一种基于网格测量的应变率计算方法，获得了切削过程应变率的分布，并与计算机模拟计算结果进行了对比分析，结果表明前刀面上的应变率受前刀面摩擦的影响，越靠近前刀面应变率越大，中心剪切面上应变率在剪切面方向上最大，且剪切面两端（刀尖与自由表面处）数值最大；从流动的观点研究应变率的分布，可实现较为粗糙的应变率定量研究。
High-speed metal cutting has been widely studied around the world for its high efficiency and quality. However, a quantitative study on many physical parameters of the cutting is still difficult when the cutting speed is high. By investigating the feasibility of studying the strain rate from the perspective of material flow, a method for strain rate calculation is proposed based on mesh measurement. The distribution of strain rate of the metal in the cutting process is obtained, and the data obtained from calculation are compared with those from measurement. The results show that the strain rate on the rake face will be affected by the friction between the chip and the tool. The nearer the distance between the chip layer and the tool rake face, the greater the strain rate will be. The strain rate in the central shear plane is much larger than that in other areas along the shear plane direction, with the strain rate in the two ends being the greatest. The quantitative study physical parameters of high-speed cutting can thus be obtained by using this method from the perspective of material flow.
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