Recently, in the aerospace industry, electrical contact materials are required to function properly under high voltage and maintain the desired properties over a prolonged period. The arc discharge inevitably occurs during the application of electrical contact materials, arc erosion plays a decisive role in the degradation of electrical contact materials. Therefore, anti-arc erosion is a major desired property of electrical contact materials. Arc can be divided into the anode area, the cathode area, and the arc column area, the cathode surface is the foundation of the emergence and development of arc. Under the effect of electric field and temperature field of comprehensive, the cathode surface continues to emit electron. The electrons form a strong collision response with the atmospheres molecules, and release a large quantity of energy. There are two distinct stages of the split arc, metal phase arc and gas phase arc. The gas phase arc predominates in electronic transmission and arc combustion. Up to now, some researches have pointed out that the same electrical contact material exhibits different electrical contact properties under different atmosphere conditions. Hasegawa et al. reported that the erosion characteristics of Ag contacts in argon was similar to that in air, but inferior to that in nitrogen. Xin et al. showed that the breaking arc duration of Cu contacts in hydrogen was considerably shorter than in air. Ghorui et al. confirmed that the erosion features of the hafnium cathode in nitrogen was superior to those in air and oxygen. Therefore, the ambient atmosphere is a critical parameter for obtaining satisfactory arc erosion performances of electrical contacts. Mn+1AXn phase is a cluster of nanolaminated ceramics, where M is a transition metal, A is a group element from IIIA to VIA, X is either carbon or nitrogen, and n is typically equal to 1, 2 or 3. Their nanolaminated hexagonal microstructures consist of Mn+1Xn carbide layers interleaved with single A atomic metallic layers. Ti3SiC2 is the classical representative of Mn+1AXn phase, it has all the characteristics of Mn+1AXn phase. The unique microstructures of the Ti3SiC2 result in the combination of both metallic and ceramic merits, such as high electrical and thermal conductivity, satisfactory corrosion and oxidation resistance, and excellent strength at high temperatures. Electrical contact materials are the critical prerequisites to conduct electricity and heat, and to interrupt high current. Due t the above-mentioned properties of Ti3SiC2, it is considere as a potential electrical contact material.
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