Electrical contact materials (ECMs) play a pivotal role in maintaining the stability and efficiency of electrical instruments and electronic devices by regulating the current flow. As an essential member of ECMs, W-Ag matrix composite ECMs (W-Ag-MC-ECMs) are integral, demonstrating commendable resistance to welding and arc erosion. However, the limited wettability between the two phases curtails their broader applications. Herein, Ag-Cu and Ag-Ni bimetallic layer-encapsulated tungsten powders were designed and successfully synthesized through a two-step electroless plating process. Subsequently, the W-Ag-MC-ECMs were fabricated following the powder metallurgy route, including the solution ball milling process and the spark plasma sintering technique. The results indicated that Cu-Ag solid solution and Ni with a metal binder effect could strengthen the interface bonding, which can dramatically improve the microhardness (up to 182HV), strength (up to 600 MPa), ductility (up to 24 %) and resistance to arc erosion (nearly two times longer service life). In addition, during the arc erosion, attributed to the Cu-Ag solid solution effect of W@Ag@Cu/Ag-MC-ECMs and solution-strengthening effect of W@Ag@Ni/Ag-MC-ECMs, the work function increases and the arc energy decreases, which reduces mass loss and extends the service life of the contacts.

中文翻译：

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设计用于增强钨银基复合电接触材料的双金属层包覆钨粉


电接触材料（ECM）通过调节电流在维持电气仪器和电子设备的稳定性和效率方面发挥着关键作用。作为 ECM 的重要组成部分，W-Ag 基复合 ECM (W-Ag-MC-ECM) 是不可或缺的，具有值得称赞的耐焊接性和耐电弧侵蚀性。然而，两相之间有限的润湿性限制了它们更广泛的应用。本文设计并通过两步化学镀工艺成功合成了Ag-Cu和Ag-Ni双金属层包覆钨粉。随后，按照粉末冶金路线制造了 W-Ag-MC-ECM，包括溶液球磨工艺和放电等离子烧结技术。结果表明，Cu-Ag固溶体和具有金属结合作用的Ni可以强化界面结合，从而显着提高显微硬度（高达182HV）、强度（高达600 MPa）、延展性（高达24%）和耐电弧侵蚀（使用寿命延长近两倍）。此外，在电弧侵蚀过程中，由于W@Ag@Cu/Ag-MC-ECMs的Cu-Ag固溶效应和W@Ag@Ni/Ag-MC-ECMs的固溶强化效应，功函数增加，电弧能量减少，从而减少质量损失并延长触点的使用寿命。