H13钢的铁基和钴基熔覆层组织与耐磨性

Microstructure and abrasion resistance of Fe-based and Co-based coatings of AISI H13

采用激光熔覆技术在AISI H13热作模具钢表面分别制备了铁基熔覆层、钴基熔覆层.借助金相显微镜、扫描电镜、洛氏硬度计和高温摩擦磨损试验机,对比分析了两种熔覆层的组织形貌、硬度和耐磨性.采用马弗炉进行加热600℃,保温1 h,反复4次,并测得红硬性硬度.结果表明,基材、铁基、钴基熔覆层硬度分别为HRC 47,HRC 52,HRC 48.基材和铁基熔覆层的红硬性硬度有所下降,而钴基熔覆层的红硬性硬度提升.钴基熔覆层磨损失重量和摩擦系数皆最小.基材、铁基熔覆层、钴基熔覆层的磨损机理分别是以磨粒磨损、粘着磨损以及粘着磨损和磨粒磨损为主.

Fe-based and Co-based cladding coatings were prepared on the surface AISI H13hot die steel by laser cladding technology.The microstructure,hardness and abrasion resistance of two kinds of the cladding coatings were compared and analyzed by an optical microscope,a scanning electron microscope,a rockwell hardness tester and a high temperature friction and wear tester.The cladding coatings were heated to600°C for1h and repeated4times by a muffle furnace.The red hardness was measured.The results showed that the hardness values of the substrate,the Fe-based and the Co-based coatings were HRC47,HRC52and HRC48,respectively.The red hardness values of the substrate and the Fe-based cladding coating decreased,while that of the Cobased coating increased.The wear loss weight and the coefficient of friction of the Co-based cladding coating were the minimum.The wear mechanisms of the substrate,the Febased and the Co-based coatings were mainly abrasive wear,adhesion wear and mixed modes,respectively.