发动机齿轮轴表面开裂原因分析  

Analysis on Cause for Surface Cracking of Engine Gear Shaft

作　　者：焦丽[1] 王国亮[1] 孙思东[1] 于曼 李珊珊 马雁军 JIAO Li;WANG Guoliang;SUN Sidong;YU Man;LI Shanshan;MA Yanjun(Hebei Huabei Diesel Engine Co.,Ltd.,Shijiazhuang 050081,Hebei China;Shanxi Diesel Engine Industry Co.,Ltd.,Datong 037036,Shanxi China)

机构地区：[1]河北华北柴油机有限责任公司,河北石家庄050081 [2]山西柴油机工业有限责任公司,山西大同037036

出　　处：《热处理》2022年第5期45-47,53,共4页Heat Treatment

摘　　要：经过渗碳、淬硬处理的发动机齿轮轴,材料为20Cr钢,磨削后发现表面有裂纹。对有表面裂纹的齿轮轴进行了宏观检验、化学成分分析、硬度检测和金相检验。结果表明:齿轮轴显微组织正常,但局部区域有变质表层。据此并结合硬度梯度可以断定,变质层由磨削烧伤造成,齿轮轴表面裂纹是磨削工艺不当所致。Engine gear shafts, made from 20 Cr steel and carburized and hardened, were found to have cracks on their surface after grinding. The gear shaft displaying surface cracks was subjected to macroscopic examination, chemical composition analysis, hardness test and metallographic test. The results showed that the gear shaft exhibited normal microstructure, but deteriorated case in some regions. In view of the above, coupled with the hardness gradient, it was concluded that the deteriorated case was caused by grinding burn, and that the formation of cracks on the gear shaft surface stemmed from improper grinding practice.

关 键 词：齿轮轴 变质层 硬度梯度 磨削烧伤 

分 类 号：TG157[金属学及工艺—热处理]