【摘要】 在Q345钢基体上采用等离子弧熔覆Fe-Ni-Cr-B-Si和Fe-Cr-B-Si两种铁基粉末涂层,制备具有冶金结合的耐磨涂层。采用光学显微镜(OM)、扫描电镜(SEM)等研究熔覆层的组织,采用X射线衍射仪对涂层进行物相分析,利用显微硬度计测试涂层的显微硬度分布。结果表明:Fe-Ni-Cr-B-Si熔覆层主要为柱状γ-Fe,局部区域为α-Fe和碳化物的网状的共晶组织;Fe-Cr-B-Si熔覆层组织主要为胞状晶,局部区域为网状的共晶组织。两种熔覆层与基材均实现了熔化冶金结合,熔覆层与母材呈联生方式长大,熔覆层的显微硬度可达500~570HV0.2,母材热影响区组织为马氏体和珠光体。更多还原

【Abstract】 By plasma cladding technology and with appropriate processing parameter,Fe-based alloy powder Fe-Ni-Cr-B-Si and Fe-Cr-B-Si were melt on the Q345,then a wear-resistant coating metallurgically bonded on the substrate was prepared.The microstructure of clad layer was investigated by optical microscope(OM),scanning electron microscopy(SEM)and X-ray diffractometer(XRD).The microhardness distribution of the clad layer was tested by microhardness tester.The results show that the microstructure of Fe-Ni-Cr-B-Si clad layer is mostly lathlikeγ-Fe,however the one of Fe-Cr-B-Si clad layer is mostly cell-like crystal,and the local area is reticulated eutectic crystal.The clad layer’s microhardness can reach 500~570HV0.2.And the microstructure of the heat-affected zone of the substrate is martensite and pearlite.更多还原