重载汽车蠕墨铸铁制动鼓的失效分析  

Failure Analysis of Heavy Duty Truck Vermicular Graphite Iron Brake Drum

作　　者：谢同轮 赵宇光[2] 李梦楠[2] 

机构地区：[1]一汽铸造有限公司铸造一厂,吉林长春130011 [2]吉林大学,吉林长春130025

出　　处：《现代铸铁》2017年第2期53-57,共5页Modern Cast Iron

摘　　要：对失效的制动鼓工作面进行宏观分析和金相检验,结果表明:蠕墨铸铁制动鼓失效的主要形式是龟裂,龟裂以工作面居多,非工作面基本无裂纹;失效后制动鼓工作面的石墨体积变粗大,部分石墨部位出现裂纹;失效后的蠕墨铸铁金相组织中珠光体分解,发生组织相变,出现大量尺寸较大的马氏体、贝氏体的混合组织;相变后的组织由于膨胀系数不同,在交变热应力的作用下基体部分出现微裂纹,这些基体微裂纹和石墨裂纹是制动鼓开裂的两大裂纹源。Metallographic examination and macro analysis were tested on failure brake drum surface. The results showed that： the main form of vermicular graphite iron brake drum failure was crack. They were mainly found on working surface and almost no crack was found on other surface. After the failure of the brake drum, graphite on working surface grown, and some cracks initiated around them. Pearlite decomposition was also found on working surface. The phase transformation result was a mixed structure of a lot of the larger martensite and bainite. Due to the different coefficients of expansion after phase transformation, microcracks initiated under alternating thermal stress. These matrix microcracks and graphite were two crack source of brake drum.

关 键 词：蠕墨铸铁 重型汽车 制动鼓 失效 

分 类 号：TG143.49[一般工业技术—材料科学与工程]