【摘要】 研究了在菱形加载路径,相同等效应力幅值(400 MPa)下,不同接触应力(50、150、250 MPa)对35CrMoA微动疲劳特性的影响。循环应力响应表明:接触应力越高,35CrMoA循环软化的程度越严重。滞后回线表明:微动疲劳的破坏主要由剪切应力引起,剪应力-剪应变循环滞后环的面积随着接触应力增大而变大。微动斑微观结果表明:当接触应力较小时,微动斑中的滑移区较宽,粘着区较窄,反之亦然;接触应力越大,微动斑磨损越严重。微动疲劳宏观断口表明:微动疲劳裂纹源萌生于微动斑,裂纹开始扩展的方向垂直于试样表面。更多还原

【Abstract】 Effects of different contact stress(50,150,250MPa)on fretting fatigue of 35 CrMoA were investigated,the study was at the same equivalent stress amplitude(400MPa)under the diamond loading path.Cyclic hardening/softening exhibited that the higher of the contact stress,the more serious of the degree of cyclic softening was.The result of hysteresis loop indicated that the fretting fatigue damage of 35 CrMoA was mainly caused by shear stress under the diamond loading path,the shear stress-strain cycle hysteresis loop areas became larger with increasing the contact stress.The SEM of fretting zone showed that when the value of contact stress was lower,the slip region in the fretting zone was wide,and the adhesive region was narrow,and vice versa.The macro fracture of fretting fatigue illustrated that the crack source was initiative at the fretting zone and the fatigue cracks in the initial phase were perpendicular to the sample surface.更多还原