60Si2CrVA弹簧钢断口及断裂原因分析  

Fracture analysis of 60Si2CrVA steel spring

作　　者：张乐[1,2] 连勇[1,2] 高文[1,2] 张津[1,2] 

机构地区：[1]北京科技大学新材料技术研究院,北京100083 [2]北京市腐蚀磨蚀与表面技术重点实验室,北京100083

出　　处：《材料热处理学报》2016年第4期149-154,共6页Transactions of Materials and Heat Treatment

基　　金：北京市腐蚀;磨蚀与表面技术重点实验室和北京市教委共建项目(SYS100080419)

摘　　要：60Si2Cr VA弹簧在服役状况下,运行寿命不到设计寿命的1/3,发生了断裂。为了分析弹簧的断口和断裂原因,根据该弹簧钢的制造和服役状况,对断口宏观形貌、SEM照片进行了分析;并对弹簧钢的应力分布、化学成分、组织和硬度进行了分析。发现了弹簧断裂为疲劳断裂,其失效起源于表面缺陷和最大切应力的共同作用,且弹簧内部组织有石墨化现象,硬度高,韧性降低,导致了整个工件的断裂。提出了该弹簧在加工过程、检测过程及热处理过程中的一些改进的措施。A 60Si2 Cr VA steel spring was fractured in service with only third of its designed service life. The failure of the spring was carried out by means of service condition analysis,chemical composition analysis of the steel,hardness test,SEM and EDS analysis. The results indicate that the fracture of the spring is caused by fatigue cracking. The fatigue crack is initiated at the surface defects with maximum shear stress. The graphitization of microstructure,high hardness,lower toughness of the steel are responsible for the spring entirely break down. Some suggestions for improvement of machining process,detection process and heat treatment are given.

关 键 词：60Si2CrVA弹簧 断口 海洋环境 热处理工艺 

分 类 号：TG142.41[一般工业技术—材料科学与工程]