For rock drilling applications, the cemented carbides containing hard WC grains in a ductile Co binder are commonly used as drill buttons. In considering the environmental and health aspects an alternate to Co-binder is pursued. In the present work, using standard scratch testing the friction and wear properties of the WC-20 vol% Ni grade is studied and compared to that of WC-20 vol% Co grade. The deformation and wear characteristics of the cemented carbide grades are evaluated and correlated to the microstructural changes during scratch testing. Also, the electrochemical impedance spectroscopy (EIS) behavior of the as-polished and scratch-tested cemented carbides was studied at the open circuit potential condition of simulated mine water (SMW) for 1 h. The obtained polarization resistance and charge transfer resistance values from the EIS analysis are correlated to the corrosion resistance of the samples. In both as-polished and scratch-tested conditions the WC-Ni grade exhibited higher polarization resistance values indicating high corrosion resistance than the WC-Co. In comparison to the as-polished sample, both the scratch-tested cemented carbides exhibited higher corrosion activity in particular within the scratch-induced tribo-layer. Severe corrosion and complete removal of the tribo-layer was observed for the WC-Co grade when exposed to SMW for 15 h. Site-specific scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) analysis were carried out to get insight into the corrosion behavior of as-polished and scratch-tested cemented carbides.

对于凿岩应用，在韧性 Co 粘合剂中含有硬质 WC 晶粒的硬质合金通常用作钻头。在考虑环境和健康方面时，正在寻求替代助粘合剂。在目前的工作中，使用标准划痕测试研究了 WC-20 vol% Ni 牌号的摩擦和磨损性能，并与 WC-20 vol% Co 牌号进行了比较。对硬质合金牌号的变形和磨损特性进行评估，并将其与划痕测试期间的微观结构变化相关联。此外，在模拟矿井水 (SMW) 开路电位条件下，研究了抛光和划痕测试硬质合金的电化学阻抗谱 (EIS) 行为 1 小时。从 EIS 分析获得的极化电阻和电荷转移电阻值与样品的耐腐蚀性相关。在抛光和划痕测试条件下，WC-Ni 等级表现出更高的极化电阻值，表明比 WC-Co 具有更高的耐腐蚀性。与抛光后的样品相比，两种经过划痕测试的硬质合金都表现出更高的腐蚀活性，尤其是在划痕诱发的摩擦层内。当暴露于 SMW 15 小时时，观察到 WC-Co 等级的严重腐蚀和摩擦层完全去除。进行了特定位置的扫描电子显微镜 (SEM) 和能量色散 X 射线光谱 (EDX) 分析，以深入了解抛光和划痕测试硬质合金的腐蚀行为。