To improve the welding resistance of Ag-8 wt%SnO contact material at large current, the graphene nanoplatelets (GNPs) was selected as the additive, and Ag-8 wt%SnO contact materials with different GNPs addition were prepared by powder metallurgy route. The electrical contact tests were performed under 36 V/16 A and 36 V/25 A, the welding, material transfer behavior and their mechanism were investigated combined with the analysis of arc duration, arc power and eroded morphology. The results show that 0.2 wt% GNPs addition decreases the welding frequency and welding force significantly, this can be attributed to the arc extinction effect and the weaken effect of the welding area. However, the excessive GNPs addition in turn aggravates the welding, the reason is that excessive GNPs addition weakens the bond between eroded layers, resulting in the decrease of arc stability and the generation of the small protrusion which cause the concentration of the contact stress and the electric field, which further results in the serious welding. Furthermore, 0.2 wt% GNPs addition decreases the mass loss rate, increasing the combination performance of Ag-8 wt%SnO contact material.

中文翻译：

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不同石墨烯纳米片添加量增强Ag-8 wt%SnO2触头材料的抗焊接和电弧侵蚀性能

为了提高Ag-8 wt%SnO触头材料的大电流耐焊接性，选择石墨烯纳米片（GNPs）作为添加剂，采用粉末冶金工艺制备了不同GNPs添加量的Ag-8 wt%SnO触头材料。在36 V/16 A和36 V/25 A下进行电接触试验，结合电弧持续时间、电弧功率和侵蚀形貌分析，研究焊接、材料过渡行为及其机理。结果表明，0.2 wt% GNPs的添加显着降低了焊接频率和焊接力，这可归因于灭弧效应和焊接区域的削弱效应。然而，过量的GNPs添加反而会加剧焊接，其原因是过量的GNPs添加削弱了侵蚀层之间的结合力，导致电弧稳定性下降，并产生小突起，导致接触应力集中，焊接性能下降。电场，进一步导致严重的焊接。此外，0.2 wt% GNPs 的添加降低了质量损失率，提高了 Ag-8 wt%SnO 接触材料的综合性能。