基于统计分析的等离子喷涂层接触疲劳寿命和失效模式

在不同应力水平下考察等离子喷涂镍基合金涂层的滚动接触疲劳寿命和失效模式。以R-3.1.1软件为平台,采用统计分析方法(方差分析、回归分析、判别分析等)对其进行分析和讨论。结果表明:涂层的滚动接触疲劳寿命呈正态分布;随着接触应力的增加,涂层的均值寿命和方差都减小,并且疲劳寿命的分布更加集中;方差分析表明,接触应力对涂层的滚动接触疲劳寿命有显著性影响,且寿命均值与接触应力具有高度的线性相关性;建立了涂层失效模式的判别准则,当指定接触应力和疲劳寿命时可以预测涂层的失效模式,且预测正确率在65%以上;疲劳寿命对失效模式的累积贡献率明显高于接触应力对失效模式的累积贡献率,因此疲劳寿命是决定涂层失效模式的主要因素。

Contact Fatigue Life and Failure M ode of Plasma Sprayed Coating Based on Statistical Analysis

The rolling contact fatigue(RCF) life and failure modes of coatings ,prepared by plasma sprayed Ni‐based alloy ,were investigated under different stress levels ,and were analyzed and dis‐cussed by statistical analysis methods (including variance analysis ,regression analysis and discrimina‐tion analysis) with R‐3 1.1. software as a platform .The results show that the RCF life of the coatings exhibits normal distribution form .In addition ,the mean and variance of the coatings’ life decreases as the contact stress increases ,and the distribution of the fatigue life becomes more concentrated .Fur‐thermore ,variance analysis indicates that the contact stress has a significant influence on the RCF life of the coatings .And the mean life of the coatings is linear associated with the contact stress .The dis‐crimination criterion for the failure modes of the coatings is also established .The failure modes of the coatings can be predicted if the contact stress and the fatigue life are designated .And the prediction accuracy of the failure mode is above 65% .Furthermore ,the contribution proportion of the fatigue life for the failure mode is obviously higher than that of the contact stress ,thus the fatigue life is the main factor determining the failure mode of the coating .