ISSN   1004-0595

CN  62-1224/O4

高级检索

CuMg0.4合金弯曲微动疲劳损伤特性研究

Bending Fretting Fatigue Damage Characteristics of CuMg0.4 Alloy

  • 摘要: 在不同参数条件下,针对吊弦用CuMg0.4合金在自主设计的弯曲微动疲劳装置上进行了微动疲劳试验,建立了其疲劳寿命S-N曲线,并结合扫描电镜(SEM)、三维轮廓仪、电子探针(EPMA)等微观分析设备对损伤区域进行了微观分析,探究了吊弦材料的弯曲微动疲劳损伤特性及演变规律. 结果显示在接触区处于弹性条件下时,其弯曲微动疲劳S-N曲线呈现倾斜的“Z”型特征,微动疲劳寿命随弯曲应力的增大呈现先减小后增大的趋势,微动依次运行于PSR(部分滑移区)、MFR(混合区)、SR(完全滑移区). 接触区主要存在磨粒磨损、氧化磨损、疲劳磨损和黏着磨损四种形式的弯曲微动疲劳损伤;微动疲劳裂纹的萌生和扩展从以接触应力控制为主逐渐转为主要受弯曲疲劳应力控制,整个过程分为三个阶段.

     

    Abstract: Under different parameter conditions, the fretting fatigue test was carried out on self-designed bending fretting fatigue device with CuMg0.4 alloy used in hanging strings. The S-N curve was built up, and the damage area was analyzed according to a series of microscopic analysis equipment, such as three-dimensional morphometer, scanning electron microscope (SEM), electron microprobe (EPMA), etc. Then the bending fretting fatigue characteristics and damage related laws of the material were discussed. The results show that when the contact area is under elastic condition. The curve of bending fretting fatigue S-N shows the characteristic of " Z”. With the increase of bending load, the fretting fatigue life of the material decrease and then increases. In turn, it runs in part of the slip regime(PSR), mixed regime (MFR)and complete slip regime(SR). The contact area includes 4 forms damage mechanism, it’s abrasive wear, oxidation wear, fatigue wear and adhesive wear. The fretting fatigue crack propagation can be divided into 3 stages, from contact stress contral to bending fatigue stress contral.

     

/

返回文章
返回