球墨铸铁镶铸硬质合金的显微组织与力学性能研究

Study on Microstructure and Mechanical Properties of Ductile Iron Insert Casting Cemented Carbide

通过在球墨铸铁中镶铸硬质合金的工艺,探究球墨铸铁与硬质合金复合界面的显微组织与力学性能。结果表明,球墨铸铁镶铸硬质合金的界面属于良好的冶金结合,复合界面通过熔合结合和扩散结合的共同作用而形成,其平均厚度为(107±14)μm。复合过渡层的组织除均匀分布的WC颗粒外,还分为两个亚组织:近球墨铸铁侧为珠光体-铁素体基体;近硬质合金侧为Co基体与珠光体-铁素体混合基体。复合界面的硬度在HV 960到HV 1104,其剪切强度为240 MPa。

The microstructure and mechanical properties of the composite interface of ductile iron and cemented carbide were explored through the process of inserting cemented carbide in the ductile iron.The results showed that the interface of the ductile iron insert cemented carbide was well bonded.The composite interface was formed by the combined action of fusion bonding and diffusion bonding,and its average thickness was(107±14)μm.In addition to the uniformly distributed WC particles,the structure of the composite transition layer was divided into two substructures:near the ductile iron side was the pearlite-ferrite matrix;near the cemented carbide side was the Co matrix and pearlite-ferrite mixed matrix.The hardness of the composite interface was between HV 960 and HV 1104,and its shear strength was 240 MPa.