两段式气体渗氮对35CrMo钢疲劳和腐蚀性能的影响  

Effect of Two Stage Gas Nitriding Process on Fatigue and Corrosion Properties of 35CrMo Steel

作　　者：杨强云 赵辉[1] 杨川[1] 曹云忠[1] 

机构地区：[1]西南交通大学材料科学与工程学院,成都610031

出　　处：《热加工工艺》2015年第12期207-210,213,共5页Hot Working Technology

摘　　要：用新研制出的两段式气体渗氮新工艺对35CrMo钢进行渗氮处理,并在一段渗氮结束后采用空冷和水冷两种冷却方式;最后对处理后35CrMo钢的组织及性能进行了分析测试。组织硬度分析表明,两种冷却方式的氮化处理均能使35CrMo钢表面获得约400μm的硬质氮化层。旋转弯曲疲劳测试表明:35CrMo钢经本次渗氮工艺处理后,其旋转弯曲疲劳周次比原材提升了将近30倍;盐雾腐蚀试验表明:35CrMo钢经本次渗氮工艺处理后,其抗腐蚀时间比原材提升了上百倍;两种渗氮处理工艺均使得35CrMo钢的疲劳性能和腐蚀性能得到大幅度提高。同时,水冷组渗氮工艺对优化35CrMo钢的腐蚀和疲劳性能比空冷组更为明显。35CrMo steel was nitrided by the new process of two stages gas nitriding, and the air cooling and water cooling were used after the first stage. The microstructure and properties of 35CrMo steel were tested and analyzed after the nitriding process. Microstructure and hardness analysis results show that the nitriding process of the two kinds of cooling methods can both let the surface of 35CrMo steel obtain a hard nitride layer which is about 400 μm. Rotating bending fatigue tests show that after the nitriding process, the rotating bending fatigue cycle number of 35CrMo steel increases nearly 30 times than before. Neutral salt spray test shows that after the nitriding process, the anti-corrosion time of 35CrMo steel increases hundreds of times than the original material. The two kinds ofnitriding process both make the fatigue and corrosion properties of 35CrMo steel improved greatly. In addition, water cooling group of nitriding process on the corrosion and fatigue performance optimization of 35CrMo steel is more obvious than air cooling.

关 键 词：气体渗氮 35CRMO钢 旋转弯曲疲劳 盐雾腐蚀 含氮马氏体 

分 类 号：TG161[金属学及工艺—热处理]