In this study, a functionally graded composite (FGC) technique is proposed to produce an electrical contact material made of W/Cu alloy. The prepared composite was sintered and subjected to high-voltage vacuum arc erosion. The composite properties and microstructure are carefully studied based on SEM images before and after exposure to vacuum arc discharge. According to the necking phenomenon observed in the electron micrographs and the quantitative analysis of the particle size, it is evident that the intermediate layer of W/Cu FGC has been in the final stage of the sintering process. The present porosity of FGC samples was less than mono-layered composite (MLC) samples, and the minimum porosity was observed in the three-layered FGC that composed of W70/Cu30 in the first layer. The average hardness of FGC samples was 4% higher than that of MLC samples with an identical composition. The results of the erosion behavior assessment were used to determine the possible arc erosion mechanism. The weight loss was diminished upon erosion when the W/Cu alloys had more than one layer, especially in four-layered FGC. The result also revealed that FGC samples, especially the four-layered composite, had improved heat transfer and prevented heat concentration on the contact surfaces due to higher content of Cu particles in the successive layers and consequently reduced the surface damage.

中文翻译：

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W/Cu功能梯度复合材料电弧腐蚀行为的制备与实验研究

在这项研究中，提出了一种功能梯度复合 (FGC) 技术来生产由 W/Cu 合金制成的电触点材料。将制备的复合材料烧结并进行高压真空电弧腐蚀。根据暴露于真空电弧放电前后的 SEM 图像仔细研究了复合材料的性能和微观结构。根据电子显微照片中观察到的颈缩现象和粒度的定量分析，可以看出 W/Cu FGC 的中间层已经处于烧结过程的最后阶段。目前 FGC 样品的孔隙率小于单层复合材料 (MLC) 样品，并且在第一层由 W70/Cu30 组成的三层 FGC 中观察到的孔隙率最小。FGC 样品的平均硬度比具有相同成分的 MLC 样品高 4%。侵蚀行为评估的结果用于确定可能的电弧侵蚀机制。当 W/Cu 合金具有超过一层时，尤其是在四层 FGC 中，侵蚀时的重量损失会减少。结果还表明，FGC 样品，尤其是四层复合材料，由于连续层中铜颗粒的含量较高，因此具有改善的传热并防止了接触表面的热量集中，从而减少了表面损伤。特别是在四层 FGC 中。结果还表明，FGC 样品，尤其是四层复合材料，由于连续层中铜颗粒的含量较高，因此具有改善的传热并防止了接触表面的热量集中，从而减少了表面损伤。特别是在四层 FGC 中。结果还表明，FGC 样品，尤其是四层复合材料，由于连续层中铜颗粒的含量较高，因此具有改善的传热并防止了接触表面的热量集中，从而减少了表面损伤。