在理论分析和实验的基础上,本文提出了以刀具磨损量的分散性随切削时间的变化趋势,即磨损量的时间稳定性作为刀具切削性能的另一个重要指标的观点。据此,并由两组短时间切削试验的结果,本文给出了两个不同的算例,估计了刀具磨损量或耐用度的条件均值和条件方差,全面比较了两种刀片的切削性能,并对“初期磨损阶段”的含义作了讨论与修正。 On the basis of theoretical analysis and experiment, this paper puts forward the viewpoint that the dispersion of tool wear varies with the cutting time, that is, the time stability of wear as another important index of tool cutting performance. Accordingly, two short examples of the results of the cutting test are given. In this paper, two different examples are given. The condition mean and the conditional variance of the tool wear or durability are estimated. The cutting performance of the two kinds of inserts is fully compared. The meaning of “initial wear stage” was discussed and amended.