钢齿轮表面合金涂层的显微结构和接触疲劳强度研究

研究了45钢齿轮轮齿表面Ni-P和Ni-Co合金涂层的显微结构和接触疲劳强度。采用电子显微镜、光学显微镜等对合金涂层进行了表面形貌、次表面组织、纵剖面界面组织、表面粗糙度、涂层的硬度和疲劳点蚀坑形貌特征的分析。接触疲劳试验结果表明，表面合金涂层能显著提高接触疲劳寿命和强度，使之与40Cr钢调质试件的相当。

The Micro-Structure and Contact Fatigue Strength of Steel Gears with Alloy Coating

This paper researched the microstructure and contact fatigue strength of Ni-P and Ni-Co alloy coating on the tooth surface of gears made from 45 carbon steel. With the help of Electron Microscope (EM) and Optical Microscope (OM), several studies on the alloying coating, such as surface shape, subsuper ficical metellographic structure, interface structure of longitudinal section, surface roughness, binding strength between alloy coating and matrix metal, element analysis of coating, microhardness and shape characteristic of fatigue pitting hole were carried out. The experimental results are analysed and conclusion is as follows: the contact fatigue life and strength of the test piece made from 45 carbon steel and treated with alloy coating were increased remarkablely than that of the test piece which have no alloy coating, their contact fatigue strength can compair with that of the test piece made from 40Cr steel with hardening and tempering.