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当两种不同的金属放在熔融的硷金属或硷土金属氯化物盐浴中时,较易腐蚀的金属会沉积在较难腐蚀的金属上。作者研究了许多这样的金属对,例如:Ti-Cu,Ti-Fe,Cr-Fe,Cr-Mo,Al-Fe,Al-Ni,Si-Fe,Si-Mo等。在这些金属对中,列在前面的金属较易被熔盐腐蚀而沉积在后面的金属上,形成扩散层,能赋予基体金属许多有用的表面性能,如抗蚀性、抗高温氧化性、抗磨耗性等。置换反应对金属沉积所起的作用很小,歧化在温度较高时有较重要的作用,而电化学作用是主要的。当阴极电流通到被腐蚀的金属时,腐蚀受到阻滞,沉积也受阻滞。反之,如果将被腐蚀的金属接为阳极,而将试样接为阴极时,沉积会加速。在熔盐中容易腐蚀的金属,例如钛,可以在熔盐中用阴极保护而进行热处理。
When two different metals are placed in a bath of molten alkali metal or alkaline earth metal chloride, the more erodible metal deposits on the less corrosive metal. The authors have studied many such pairs of metals such as Ti-Cu, Ti-Fe, Cr-Fe, Cr-Mo, Al-Fe, Al-Ni, Si-Fe, Si-Mo and the like. Among these metal pairs, the front-most metals are more likely to be attacked by molten salt and deposited on the rear metal to form diffusion layers that impart many useful surface properties to the base metal such as corrosion resistance, high temperature oxidation resistance, Wear and so on. Displacement reaction on the role of metal deposition is very small, disproportionation at higher temperatures have a more important role, while the electrochemical role is the main. When the cathodic current passes through the corroded metal, the corrosion is blocked and the deposition is blocked. Conversely, if the metal to be corroded as the anode, and the sample is connected to the cathode, the deposition will accelerate. Metals that are easily corrosive in molten salts, such as titanium, can be heat treated with cathodic protection in the molten salt.