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采用高速电弧喷涂技术及钨极氩弧重熔技术分别制备Fe-Cr-B喷涂层及其重熔层,采用X射线衍射仪、金相显微镜、X射线残余应力测试仪、显微硬度仪、动载磨料磨损试验机、扫描电子显微镜分别对喷涂试样及重熔试样的相结构、微观组织、残余应力、纵截面硬度、耐磨性及磨损表面形貌进行观察与测试。结果表明,重熔处理后,电弧喷涂Fe-Cr-B涂层的组成由Fe基非晶和硼化物相转为Cr_2B、(Cr,Fe)_2B、α-Fe相,涂层与基体由机械结合转为冶金结合,重熔试样由表层至基体的显微组织分别是初生硼化物以及共晶组织、共晶硼化物+马氏体+奥氏体、初生奥氏体以及共晶组织、热影响区组织。重熔处理后,涂层显微硬度由689 HV0.1上升为960 HV0.1,磨损失重率由0.088 g/(cm~2·min~(-1))降为0.004 6 g/(cm~2·min~(-1))。喷涂层的磨粒磨损机制主要是微断裂,重熔层的磨粒磨损机制主要是变形磨损和微切削。
Fe-Cr-B sprayed layer and its remelted layer were prepared by high-speed arc spraying and TIG arc remelting technique respectively. X-ray diffraction, metallographic microscope, X-ray residual stress tester, microhardness tester, Dynamic wear abrasive wear testing machine and scanning electron microscope were used to observe and test the phase structure, microstructure, residual stress, longitudinal section hardness, wear resistance and wear surface morphology of sprayed sample and remelted sample respectively. The results show that the composition of the arc sprayed Fe-Cr-B coating is changed from Fe-based amorphous and boride to Cr_2B, (Cr, Fe) _2B and α-Fe phases after remelting. Combined with the combination of metallurgical bonding, the microstructure of the remelted specimen from the surface to the matrix is primary boride and eutectic, eutectic boride + martensite + austenite, primary austenite and eutectic, respectively, Heat affected zone organization. After remelting, the microhardness of the coating increased from 689 HV0.1 to 960 HV0.1, and the weight loss rate decreased from 0.088 g / (cm ~ 2 · min -1) to 0.004 6 g / (cm ~ 2 · min ~ (-1)). Abrasive wear mechanism of the spray coating is mainly micro-fractures, and the abrasive wear mechanism of the remelt layer is mainly deformation and micro-cutting.