发动机齿轮“点蚀”的正交试验研究

Orthogonal Experimental Investigation on Pitting Corrosion of Engine Gear

评定碳氮渗齿轮质量好坏的主要参数是渗层深度、表面碳浓度及渗层碳浓度梯度。而要获得较为准确的渗层深度,合适的表面碳浓度及平缓的碳深度梯度,除了要有正确的碳势、温度、渗碳总时间外,还要有合适的强渗时间与扩散时间之比。齿轮早期磨损点蚀的原因很多,齿轮精度、材料和热处理规范及润滑油选择不当都会造成齿轮早期磨损点蚀。研究齿轮渗碳层深度超出21.67%是否会导致齿轮点蚀,通过正交试验、工艺参数研究及金相检测分析,碳化物的分析,找出了合适的工艺参数。

Carbonitriding layer depth, surface carbon concentration and concentration grads of carbonitriding layer are the main parameters to evaluating the quality of carbonitriding gear. To obtain suitable values of the three parameters, appropriate ratio of permeation/diffusion time is required besides proper carbon potential, temperature and the whole carburizing time. There are many reasons for early wearing and pitting corrosion of gear, such as gear precision, material, thermal-treatment and the oil selection. Whether the pitting corrosion of gear could be caused if Carbonitriding layer depth is over 21.67% is investigated. Orthogonal Experiment, process parameters study, metallography detection and carbonitride analysis are carried out. Proper process parameters are determined.