标题: Anodic carbidation of tantalum in molten CaCl2 -CaC2

作者: Zhao, MY (Zhao, Meiyu); Du, P (Du, Pin); Liu, W (Liu, Wei); Du, KF (Du, Kaifa); Ma, YS (Ma, Yongsong); Yin, HY (Yin, Huayi); Wang, DH (Wang, Dihua)

来源出版物: JOURNAL OF SOLID STATE ELECTROCHEMISTRY  DOI: 10.1007/s10008-022-05126-w 提前访问日期: JAN 2022

摘要: Making a tantalum carbide (TaC) coating on Ta substrates is an effective way to improve the mechanical and anti-corrosion properties of Ta. However, conventional methods for making a TaC coating require high-temperature conditions of over 1600 degrees C to get a TaC thickness of >20 mu m. Herein, a TaC coating of > 20 mu m thickness was prepared on a Ta substrate in molten CaCl2-CaC2 at 850 degrees C for 4 h. In the molten salt electrolyzer, the Ta plate served as the anode where C-2(2-) was oxidized and simultaneously reacted with Ta to form a TaC layer, and Ca2+ was reduced and alloyed with C to form CaC2 that can replenish the C-2(2-). The electrolytic TaC exhibited an average hardness of 962 HV that was 6 times of the bare Ta substrate. In the 3.5 wt% NaCl solution, the TaC coating displayed a higher corrosion potential and lower corrosion current density (0.48 V, 1.59 mu A cm(-2)) than Ta substrate (0.35 V, 1.85 mu A cm(-2)) and the mixtures of TaC and Ta2C (0.35 V, 1.78 mu A cm(-2)), indicating its better corrosion resistance. The molten salt anodic carbidation may lead to a general way to prepare transition metal carbide coatings with enhanced carburizing kinetics at < 1000 degrees C.

作者关键词: Molten salt electrolysis; Anodic carbidation; Tantalum carbides; Hardness; Corrosion behaviors

地址: [Zhao, Meiyu; Du, Pin; Liu, Wei; Du, Kaifa; Ma, Yongsong; Yin, Huayi; Wang, Dihua] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

通讯作者地址: Wang, DH (通讯作者)，Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

电子邮件地址: wangdh@whu.edu.cn

影响因子：2.647