不同粘结相含量WC-Co和WC-Ni-Fe硬质合金的微观组织及性能差异研究

Study on Microstructure and Properties of WC-Co and WC-Ni-Fe Cemented Carbides with Different Binder Phase Contents

摘要:

采用同一工艺制备了两组不同粘结相含量的WC-Co和WC-Ni-Fe硬质合金，研究了WC-Co和WC-Ni-Fe硬质合金的组织结构变化趋势及性能差异，结果表明，两组WC-Co和WC-Ni-Fe硬质合金的粘结相均为单相结构，粘结相含量增加会引起合金平均晶粒尺寸的增大，在性能上表现为硬度、矫顽磁力下降，而钴磁、抗弯强度和冲击韧性均呈上升趋势。同一粘结相含量下，WC-Co硬质合金的钴磁、矫顽磁力、抗弯强度均高于WC-Ni-Fe硬质合金。粘结相含量较高时，WC-Ni-Fe硬质合金则展现出更好的冲击韧性，最高可达5.9 J/cm²。WC-Co和WC-Ni-Fe硬质合金具有相似的摩擦磨损行为，随着粘结相含量的增加，合金的磨损程度逐步加剧。当合金中具有相同的粘结相含量时，WC-Co硬质合金的耐磨性略好于WC-Ni-Fe硬质合金。

Abstract:

Two groups of WC-Co and WC-Ni-Fe cemented carbides with varying binder phase contents were prepared using the same process. The research explored the trends in the microstructure changes and the differences in properties between WC-Co and WC-Ni-Fe cemented carbides. The results show that the binder phase of both WC-Co and WC-Ni-Fe cemented carbides exhibits a single-phase structure. As the binder phase content in the alloy increases, there is an increase in average grain size and a decrease in hardness and coercive magnetic force. Additionally, cobalt magnetism, bending strength, and impact toughness all exhibit upward trends. In comparison, the WC-Co cemented carbide exhibits higher coercive cobalt magnetism, magnetic force, and bending strength than WC-Ni-Fe cemented carbide. However, WC-Ni-Fe cemented carbide exhibits better impact toughness with a higher binder phase content, reaching up to 5.9 J/cm². The frictional behavior of WC-Co and WC-Ni-Fe cemented carbides is similar, but the wear degree of the alloys gradually increases as the binder phase content increases. When the contents of binder phase content are the same, the wear resistance of WC-Co cemented carbide is superior to that of WC-Ni-Fe cemented carbide.