全属切削过程的实质是工件材料在刀具切削刃和前刀面挤压作用下的塑性剪切变形过程,这个变形区称之为第一变形区,它可用假想剪切面来表示。本文较详细的讨论了剪切面的形状,证明了假想剪切面为曲面形状及其修正计算方法,这将对切削基础理论有关方面的研究起到促进和完善作用。 The whole process of cutting is the essence of the workpiece material in the cutter cutting edge and rake face under the action of plastic shear deformation process, the deformation zone called the first deformation zone, which can be used to represent the imaginary shear plane. This paper discusses the shape of the shear plane in more detail, and proves that the imaginary shear plane is the shape of the curve and the method of its correction, which will promote and perfect the research on the basic theory of cutting.