摘要
采用含０．４４％ Ｃ 的车轴钢，按实物车轴与试样尺寸４∶１ 制成模拟试验轴，将 Ｆｅ、 Ｎｉ、 Ｃｒ及 Ａｌ合金粉末喷涂于试验轴表面，采用模拟轮对试验轴进行模拟车轴工况的微动损伤试验．采用扫描电镜和 Ｘ 射线光电子能谱仪分析涂层磨损表面的氧化物和磨屑表面形貌， Ｘ 射线衍射仪分析磨屑的组织结构．结果表明：涂层磨损表面平滑致密的氧化层中发生龟裂，磨损较为严重；涂层磨损以氧化和表面剥离为主，轴表面无裂纹．其原因在于涂层的层状结构有利于阻止微动作用下表面裂纹向纵深扩展形成疲劳裂纹，提高了车轴的抗微动疲劳能力和使用寿命．
The tested specimen was made by using 0.44% C axial steel with a size ratio of real axle to specimen four to one. Fe、Ni、Cr、Al alloy powder was thermally sprayed on to the specimen. Fretting test was carried out on the simulator of wheel and axle in working condition to investigate the fretting mechanism of the coating and the effect of thermal spraying on the fretting fatigue resistance of the axle. Scanning electron microscope (SEM) and X ray photoelectron spectroscope (XPS) were used to examine the appearance of the fretted axial surface and wear debris. Optical microscope and X ray diffraction (XRD) were used to identify the structures of the coating and wear debris.It has been found that slip, mixed, and stick fretting regimes can be identified on the coating surface.Severe wear,cracks,thicker smooth oxide film, and work hardening were observed on the fretted surface.The fretting behavior of the coating was characteristic of exfoliation of the superficial oxides and work hardened metals. Brittle cracks were observed on the exfoliated debris. There were no cracks on the axial surface.It was supposed that the layer structure of the coating was beneficial to resisting the development of the superficial fretting cracks into axial fatigue cracks.
出处
《摩擦学学报》
EI
CAS
CSCD
北大核心
1999年第3期234-238,共5页
Tribology
基金
铁道部科技项目资助
