Erosion craters on Ti3SiC2 anode

Erosion of Cu–Ti3SiC2 composite under vacuum arc

“…In this study and our previous reports, dissociation of Ti 3 SiC 2 under the impact of vacuum arc was confirmed [16,17]. The Ti 3 SiC 2 decomposition process needs to absorb a great deal of heat (DG 1600K ¼ 181 kJ mol À1 ).…”

“…However, no peaks of Ti 3 SiC 2 , TiC, C and even Si or Ti containing compounds can be found in either electrode. As mentioned in our previous report [16,17], Ti 3 SiC 2 is unstable under the impact of the vacuum arc. The dissociation of Ti 3 SiC 2 takes place at cathode surface and results in the formation of TiC x and C. In this investigation, only peaks of Cu and Mo are found on the electrodes' surface after 1000 times of electrical breakdowns.…”

“…The detected C may result from the decomposed and/or remaining Ti 3 SiC 2 , or even from the surface contamination with C-containing compounds. In our previous reports, micro-Raman spectroscopy results revealed that small amounts of amorphous carbon appeared as a by-product of the Ti 3 SiC 2 dissociation [16,17]. Although EDS cannot give quantitative result on light elements such as C, the high C concentration in Point 4 (47.82 at%C, 5.69 at%Ti, 2.52 at%Si, 43.97 at%Cu) and the low solubility of C in Cu (from the CueC phase diagram) may suggested the presence of C in the melted Cu.…”

“…A typical EDS point analysis on these erosion pits show that it composed of 9.72 at% Cu, 45.65 at% Ti, 7.41 at% Si and 37.22 at% C. The lack of Si in the erosion pits appears to be a result of the decomposition of Ti 3 SiC 2 . In our former investigations [16,17], we have reported the decomposition of Ti 3 SiC 2 under vacuum arc. Due to the extreme temperature of the arc spots, Ti 3 SiC 2 decomposed into TiC x as the major detectable product.…”

“…In order to evaluate the composite's performance under vacuum breakdown, the influence of vacuum arc on the phase stability of CueTi 3 SiC 2 composite need to be examined. We have reported previously the erosion behavior and the phase stability of pure Ti 3 SiC 2 under the impact of vacuum arc [16,17]. Results of these articles show that Ti 3 SiC 2 is unstable under vacuum arc.…”