Electrochemical corrosion behaviors of Ti₃SiC₂/Cu composites in a 3.5% NaCl solution

Abstract

The electrochemical corrosion behaviors of Ti 3 SiC 2 /Cu composite and polycrystalline Ti 3 SiC 2 in a 3.5% NaCl medium were investigated by dynamic potential polarization, potentiostat polarization, and electrochemical impedance spectroscopy. The polycrystalline Ti 3 SiC 2 was tested on the identical condition as a control. The characterizations of XRD, X-ray photoelectron spectroscopy, scanning electron microscope, and energy-dispersive spectrometer were used to study the relevant passivation behavior and corrosive mechanism. The self-corrosion current density of Ti 3 SiC 2 /Cu (6.46 × 10 −6 A/cm 2 ) was slightly higher than that of Ti 3 SiC 2 (1.64 × 10 −7 A/cm 2 ). Under open circuit potential, the corrosion resistance of Ti 3 SiC 2 /Cu was better than that of Ti 3 SiC 2 . Ti 3 SiC 2 /Cu exhibited a typical passivation feature with a narrow passivation interval and a breakdown phenomenon. The better corrosion resistance of Ti 3 SiC 2 was due to the more stable Si layer of the former. In comparison, for Ti 3 SiC 2 /Cu composites, Cu reacted with the reactive Si layers in Ti 3 SiC 2 to form Cu-Si compounds and TiC, destroying the weak interaction between Si layers and Ti-C layers. In the other hand, the as-formed Cu-Si compounds and TiC dissolved during the corrosion of Ti 3 SiC 2 /Cu in the 3.5% NaCl medium, causing to the destruction of the passivation film on its surface.

Effects of Ti ion deposition on corrosion resistance of WE43 alloy

“…The I corr value is an important parameter that indicates the corrosion rate of the alloy. The larger the I corr value, the worse the corrosion resistance of the film 27 . It can be seen from Table 3 that with the increase of Ti ion deposition time, the I corr value of WE43 alloy first decreases and then increases.…”

“…The larger the I corr value, the worse the corrosion resistance of the film. 27 It can be seen from Table 3 that with the increase of Ti ion deposition time, the I corr value of WE43 alloy first decreases and then increases. When the deposition time is 800 s, the I corr value of Ti800 alloy is the smallest (2.9 μA⋅cm −2 ), which is two orders of magnitude lower than that of WE43 alloy, showing good corrosion resistance.…”

Corrosion behaviors of Ti3SiC2/Cu composites in molten salts

“…As a typical MAX, Ti 3 SiC 2 exhibited good arc erosion resistance, good conductivity, good thermal conductivity, and good tribological property, thus it was expected to be used as electrically conductive materials and applied in modern industries, such as high‐speed railway, military industry, and aerospace and electrical manufacturing 4–8 . Compared with the present widely applied Cu‐based electrically conductive materials, the conductivity of single Ti 3 SiC 2 was not satisfied 9–12 . Afterwards, Ti 3 SiC 2 based composites intensified by Cu exhibited excellent tribological properties, corrosion resistance, arc ablation resistance, excellent electrical and thermal conductivity, therefore, they had been widely researched.…”

“…[4][5][6][7][8] Compared with the present widely applied Cu-based electrically conductive materials, the conductivity of single Ti 3 SiC 2 was not satisfied. [9][10][11][12] Afterwards, Ti 3 SiC 2 based composites intensified by Cu exhibited excellent tribological properties, corrosion resistance, arc ablation resistance, excellent electrical and thermal conductivity, therefore, they had been widely researched. They were developed to meet the requirement of modern electrically conductive materials.…”