挖掘机链轨节失效分析及改善  

Failure analysis and improvement of excavator track links

作　　者：吴爱青 杨小芳[1] 孙叶[1] 范宪勇 李晨 张鲁惠燕先 WU Aiqing;YANG Xiaofang;SUN Ye;FAN Xianyong;LI Chen;ZHANG Lu;HUI Yanxian(Shantui Construct Machinery Co.,Ltd.,Jining 272000,Shandong,China)

机构地区：[1]山推工程机械股份有限公司,山东济宁272000

出　　处：《金属加工(热加工)》2025年第4期156-160,166,共6页MW Metal Forming

摘　　要：挖掘机履带链轨节在服役过程中出现裂纹及掉块等失效问题。通过化学成分、硬度、微观组织、断口形貌、有限元等检测对链轨节进行全面失效分析。结果表明:链轨节裂纹为疲劳裂纹,其结构上存在应力集中区域;剖检分析发现,其调质晶粒度及硬化区马氏体组织较为粗大,其他检测项目均无明显异常。基于分析结果,进行设计优化避免应力集中区域,并且通过改善调质工艺来提高基体晶粒度,改善踏面硬化工艺以细化马氏体组织。通过以上改善措施加强链轨节的强韧性、抗冲击性等综合性能,链轨节裂纹掉块失效问题得到显著改善。During the service life of the excavator crawler track link,failure problems such as cracks and chipping occur.A comprehensive failure analysis of the track link is carried out through tests of chemical composition,hardness,microstructure,fracture morphology,finite element,etc.The results show that the cracks in the track link are fatigue cracks,and there are stress-concentration areas in its structure.Through dissection analysis,it is found that the tempered grain size and the martensite structure in the hardened area are relatively coarse,while there are no obvious abnormalities in other inspection items.Based on the analysis results,design optimization is carried out to avoid stress-concentration areas.Moreover,the matrix grain size is improved by optimizing the quenching and tempering process,and the martensite structure is refined by improving the tread hardening process.Through the above improvement measures,the comprehensive properties of the track link,such as strength,toughness,and impact resistance,are enhanced,and the failure problems of cracks and chipping of the track link are significantly improved.

关 键 词：履带 链轨节 裂纹 失效 调质 

分 类 号：TG115.5[金属学及工艺—物理冶金] TG142.1[金属学及工艺—金属学]