QT500-7球墨铸铁行星架断裂原因  

Reasons for fracture of QT500-7 ductile iron planetary carrier

作　　者：冯志明 薛文璞 冯银平 张沈洁 王小培 左毅 FENG Zhiming;XUE Wenpu;FENG Yinping;ZHANG Shenjie;WANG Xiaopei;ZUO Yi(First Tractor Company Limited,Luoyang 471004,China;National Industrial Measurement and Testing Center for Agricultural Machinery Equipment,Luoyang 471004,China;Luoyang Key Laboratory of Mechanical Product Failure Analysis,Luoyang 471004,China)

机构地区：[1]第一拖拉机股份有限公司,洛阳471004 [2]国家农机装备产业计量测试中心,洛阳471004 [3]洛阳市机械产品失效分析重点实验室,洛阳471004

出　　处：《理化检验(物理分册)》2025年第4期55-58,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：拖拉机用球墨铸铁行星架在使用约400 h后发生断裂事故。采用宏观观察、扫描电镜分析、力学性能测试、金相检验等方法对行星架的断裂原因进行分析。结果表明:行星架的力学性能低于标准要求,同时存在严重的夹渣、缩孔和疏松等铸造缺陷,破坏了铸件材料内部组织的连续性和致密度,减小了铸件的有效承载面积,降低了零件的强度,铸造缺陷位置产生应力集中,最终造成行星架发生早期脆性断裂。The ductile iron planetary carrier used in tractors cracked after approximately 400 hours of use.The fracture reasons of the planetary carrier were analyzed using macroscopic observation,scanning electron microscopy analysis,mechanical property,testing,metallographic examination.The results show that the mechanical properties of the planetary carrier were lower than the standard requirements,and there were serious casting defects such as slag inclusion,shrinkage,and unsoundness,which destroyed the continuity and density of the internal structure of the casting material,reduced the effective bearing area of the casting,lowered the strength of the parts,and caused stress concentration at the location of casting defects,ultimately led to early brittle fracture of the planetary carrier.

关 键 词：QT500-7球墨铸铁 行星架 铸造缺陷 早期脆性断裂 显微组织 力学性能 

分 类 号：TB31[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]