B_4C对汽车缸套激光熔覆修复涂层组织与性能的影响  

Effects of B_4C on Microstructure and Properties of Laser Cladding Coating for Automobile Cylinder

作　　者：唐利平 刘海雄 李雪丰 

机构地区：[1]湖南汽车工程职业学院,湖南株洲412001 [2]昌河铃木汽车有限责任公司,江西九江332005

出　　处：《热加工工艺》2016年第14期124-126,共3页Hot Working Technology

摘　　要：采用激光熔覆方法在缸套材料表面制备出高强高硬度耐磨涂层。使用光学显微镜、洛氏硬度计、磨粒磨损试验机等仪器研究了B_4C含量对涂层组织和性能的影响。结果表明:当B_4C含量为0时,涂层组织为铁素体和指纹状的共晶组织α-Fe+M_(23)C_6或α-Fe+M_3(C,B)。当B_4C含量从0增加到9%时,初生碳化物M_(23)C_6含量与晶粒尺寸都增大,而涂层硬度与耐磨性则先增加后减小。当B_4C含量为0时,其耐磨性只有基体的10倍左右。当B_4C含量为6%时,其相对耐磨性大大增加,是基体的28倍左右。The coating with high strength, high hardness and high wear resistance was prepared by laser cladding on the surface of automobile cylinder material. Effects of B4C content on the microstructure and properties of the coating were investigated by optical microscopy, Rockwell hardness tester and wet sand rubber wheel tester. The results show that the microstructure is α-Fe and fingerprint eutectic structure of α-Fe＋M23C6 or α-Fe＋M3 （C, B） when the B4C content is 0. When B4C content increases from 0 to 9%, the content and grain size of carbide M23C6 increase. The hardness and wear resistance of the coating increase at first and then decrease. When B4C content is 0, the relative wear resistance is about 10 times of that of substrate. When B4C content is 6%, the relative wear resistance is about 28 times of that of substrate.

关 键 词：气缸套 激光熔覆 B4C 耐磨性 

分 类 号：TG174[金属学及工艺—金属表面处理]