卡车制动盘的开裂失效分析  

Analysis on Cracking Failure of Truck Brake Disc

作　　者：卢松涛[1] LU Song-tao(College of Mechanical Engineering,Shangqiu Insititute of Technology,Shangqiu 476000,China)

机构地区：[1]商丘工学院机械工程学院

出　　处：《材料保护》2019年第11期170-173,共4页Materials Protection

摘　　要：制动盘在使用过程中出现了碎裂,对此进行了失效分析。结果表明:其石墨形态为A形石墨+C形石墨,A型石墨占90%,石墨长度为3级,硬度为210 HB,均符合相关技术要求;基体显微组织为铁素体+珠光体,有明显的树枝晶,说明存在铸造缺陷;利用扫描电镜对裂纹处进行微观形貌和能谱分析,存在较多的氧化物;由于制动盘本身存在铸造缺陷、再加上热疲劳和腐蚀坑的综合作用,导致出现了早期开裂失效。The brake disc was broken in the service and the fracture failure analysis was carried out.Results showed that the graphite morphology was A-shaped graphite+C-shaped graphite.Type A graphite accounted for 90%,and the length of graphite was grade 3,as well as the hardness was 210 HB,which all met the relevant technical requirements.The microstructures of the matrix were ferrite+pearlite with obvious dendrite,which indicated that there were casting defects.SEM and EDS were used to analyze the microstructure and the elements content of the cracks,and more oxides were found.The brake disc itself had casting defects,combined with thermal fatigue and corrosion pits,which led to early cracking failure.

关 键 词：制动盘 灰铸铁 热疲劳 树枝晶 失效分析 

分 类 号：TG115[金属学及工艺—物理冶金]