近几年来,在一系列的著作中确定了金属在塑性变形过程中的几个特点.从这些著作中得出最重要的结论是证实了金属在拉伸曲线各阶段中的变形是不均匀的.从按试样长度变形的分布情况来看,一般拉伸曲线图,由下列四个阶段组成,如图1所示. In recent years, several features of the metal during plastic deformation have been identified in a series of works, and the most important conclusion from these works is that it confirms that the deformation of the metal in various stages of the tensile curve is not uniform From the distribution of deformation according to the length of the sample, the general tensile curve consists of the following four phases, as shown in Figure 1.