Ti_(3)AlC_(2)陶瓷及其衍生物Ti_(3)C_(2)T_(x)增强的Ag基电接触材料

Ag-based Electrical Contact Material Reinforced by Ti_(3)AlC_(2) Ceramic and Its Derivative Ti_(3)C_(2)T_(x)

银基电触头在低压开关领域扮演重要角色。作为一种具有良好导电导热性能的新型二维碳化物材料,MXene家族典型代表材料(Ti_(3)C_(2)T_(x))在多个领域显示出极大的应用潜力。Ti_(3)C_(2)T_(x)有望作为一种新型环保银基电触头增强相材料。本研究采用粉末冶金法制备了Ag/Ti_(3)C_(2)T_(x)复合材料,并对Ti_(3)C_(2)T_(x)和Ti_(3)AlC_(2)的物相和微观结构进行表征。同时研究了Ti_(3)C_(2)T_(x)增强Ag基复合材料的综合性能,包括电阻率、显微硬度、机械加工性能、抗拉强度和抗电弧侵蚀性能,并与Ti3Al C2增强Ag基复合材料进行了比较。Ag/Ti_(3)C_(2)T_(x)的电阻率(30×10^(–3)μΩ·m)相对于Ag/Ti_(3)Al C_(2)(42×10^(–3)μΩ·m)降低了29%。Ag/Ti_(3)C_(2)T_(x)硬度适中(64HV),具有良好的可加工性,作为无毒电触头材料应用前景广阔。Ag/Ti_(3)C_(2)T_(x)复合材料导电性能的提高主要归因于Ti_(3)C_(2)T_(x)本身优异的金属性以及由Ti_(3)C_(2)T_(x)微观结构特征带来的可变形性。由于缺乏Al-Ag相互扩散,Ag/Ti_(3)C_(2)T_(x)复合材料的拉伸强度(32.77MPa)明显低于Ag/Ti_(3)Al C_(2)复合材料(145.52 MPa)。正因为缺失Al层,Ag/Ti_(3)C_(2)T_(x)的抗电弧侵蚀性能也无法与Ag/Ti_(3)AlC_(2)相媲美。尽管Ag/Ti_(3)C_(2)T_(x)的抗电弧侵蚀性能有待进一步提高,但优异的导电性使其有望替代有毒的Ag/CdO电接触材料。该研究结果为开发新型环保电触头材料提供了新的探索方向。

Ag-based electrical contact plays a key role in low-voltage switches, which is intended to substitute the traditional and toxical “universal” contact of Ag/CdO. As a new kind of two-dimensional carbide material with good electrical conductivity and thermal conductivity, Ti_(3)C_(2)T_(x), a representative of MXenes has showed exceptional potential in various fields, including being the reinforcement phase in electrical contact materials to substitute for the toxic Cd O. In this work, we successfully prepared Ag/Ti_(3)C_(2)T_(x)composite by powder metallurgy. Phase and microstructure of the Ti_(3)C_(2)T_(x)and Ti;Al C;were characterized, and their properties, such as electrical resistivity, microhardness, machinability, tensile strength, and anti-arc erosion performance were investigated and compared. The Ag/Ti_(3)C_(2)T_(x)has a resistivity of 30×10^(–3)μΩ·m, 29% lower than that ofAg/Ti_(3)Al C_(2)(42×10^(-3)μΩ·m) and excellent machinability with intermediate microhardness(64 HV), showing broad application prospect as non-toxic electrical contact materials. Its improved conductivity is mainly attributed to the metallicity of Ti_(3)C_(2)T_(x)itself, the microstructural features, endowed by the deformability of Ti_(3)C_(2)T_(x). However, the tensile strength(32.77 MPa) of Ag/Ti_(3)C_(2)T_(x)is inferior to that of Ag/Ti_(3)AlC_(2)(145.52 MPa) due to lack of Al-Ag interdiffusion. The anti-arc erosion performance of Ag/Ti_(3)C_(2)T_(x)is also unmatchable with Ag/Ti_(3)AlC_(2)due to absence of Al layer. Although the arc erosion resistance of Ag/Ti_(3)C_(2)T_(x)needs to be further improved uptill now, the significantly improved electrical conductivity makes it a potential substitute of current toxic Ag/CdO material. All results of this work provide an exploration direction for developing new environmentally friendly electrical contact material in the future.