35CrMoA微动疲劳特性及其微结构研究

The fretting fatigue behaviour of 35CrMoA and its microstructure

通过平面对平面的接触方式,研究35CrMoA微动疲劳特性及其微结构,通过透射电镜(TEM)观察并分析了微动疲劳过程中不同接触应力及不同循环周次时接触区位错的组态。结果表明,随着接触应力的增大,其寿命不断降低,但在不同接触应力区间内,疲劳寿命降低的趋势不同;随着微动疲劳周次增加,其位错密度逐渐增大并互缠结在一起,进一步演化为位错胞;在不同接触应力下,微动疲劳后期都形成了位错胞结构;微动疲劳表层发现有层错亚结构,并且微动接触区的表层容易形成驻留滑移带。

The fretting fatigue behavior of 35CrMoA and its microstructure were investigated by the means of plane to plane contact.Dislocation structure at the contact area was observed by transmission electron microsco-py （TEM）,and analyzed at different contact stress and different cycles during the process of fretting fatigue. The results indicate that the fretting fatigue life of 35CrMoA decreases with the contact stress increasing.How-ever,the fatigue life reduction trend was different at the different contact stress range;With the increase of fretting fatigue cycle,the density of dislocation increases gradually and dislocations are intertwined mutually, further form the dislocation cell;dislocation cells are all formed in the late of fretting fatigue at different contact stress;stacking fault substructure was also found in the surface layer of fretting fatigue,and persistent slip band was easy to form in the surface layer of the fretting fatigue contact area.