The effects of magnetic quenching on the performance and structure of YG6 (WC-6%Co) and YN6 (WC-6%Ni) cemented carbides were studied using powder X-ray diffraction, scanning electron microscope, optical microscope, transverse rupture strength, Vickers hardness and coervice force tests. The research conditions are: samples are held at (1 100±5) ℃ for 20-25 min, magnetic quenched for 15 min with 2 T intensity, then annealed at temperature (500±5) ℃ for 3 h. Conventional quenching treatment with YG6 (WC-6%Co) was also conducted. The results show that after magnetic quenching, Vickers hardness of YG6 increases by 3%, transverse rupture strength increases by 18%, impact toughness increases by 24%, cocrvice force increases by 25%; while transverse rupture strength of YN6 increases by 5.9%, impact toughness increases by 6.9%, and there is no significant change in Vickers hardness and coervice force of YN6. The content of α-Co in WC-Co alloy increases, solid solubility of W and C increases and the degree of the rounding of the edges and corners of carbide crystals tends to increase after magnetic quenching; and WC presenting serration feature while deflecting to ordered direction is the main reason for performance improving.%采用X线衍射(XRD)、扫描电镜(SEM)、金相(OM)、横向断裂强度、维氏硬度以及矫顽磁力测试等分析手段,研究YG6(WC-6％Co)及YN6(WC-6％Ni)合金在磁场淬火处理后的性能变化规律.研究的条件为:样品在(1 100±5)℃下保温20～25 min,在脉冲磁场强度2T下淬火15 min后再(500±5)℃回火3h;此外对YG6合金进行常规淬火比较.研究结果表明:磁场淬火可使YG6合金维氏硬度提高3％、横向断裂强度提高18％、冲击韧性提高24％、矫顽磁力提高25％；而YN6合金横向断裂强度提高5.9％,冲击韧性提高6.9％,维氏硬度和矫顽磁力无明显变化.磁场淬火使钴基硬质合金的黏结相中α-Co含量提高,W和C在黏结相中的固溶度增加,WC晶粒棱角趋于圆滑:同时,磁场引起钴基硬质合金中WC晶粒出现锯齿状形貌并偏转为有序方向排列,是合金性能改善的主要原因.
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