摘要
采用渗硅碳化硅作为试样,以600～800℃的熔融锌液作为腐蚀介质,用浸泡法测定了试样在高温熔融锌液中的腐蚀速率,并与1Cr18Ni9Ti不锈钢试样进行了比较。通过扫描电镜对不同条件下腐蚀机制进行探讨。试样在锌液中的腐蚀速率由失重法计算。通过对在不同温度和不同腐蚀时间的不锈钢与渗硅碳化硅(SiC)试样的腐蚀试验,可以发现,对于不锈钢,锌液腐蚀主要以溶解腐蚀形式为主;不锈钢试样的腐蚀速率远远大于碳化硅试样,在600℃时,不锈钢材料的腐蚀速率比碳化硅材料高2个数量级,在700℃时,不锈钢试样在8h就全部溶解,而在750、800℃时,试样在不到5 h全部溶解。而对于渗硅碳化硅试样,试样的腐蚀是以试样裂纹剥落和溶解共同作用。腐蚀机制依赖于锌液腐蚀温度,当锌液温度小于750℃时,腐蚀是以剥落和溶解共同作用,硅的溶解腐蚀现象较低,试样的腐蚀速率很小;SiC试样在750℃,8h的腐蚀速率仅0.6%;当锌液温度大于800℃时,腐蚀主要以硅的溶解腐蚀为主,腐蚀速率大幅度增加,试样在800℃,8h的腐蚀速率达到3%。
The permeability silicon SiC and stainless steel 1Cr 18Ni9Ti were adopted, and the corrosion experiments were carried out at 600 ℃ -800 ℃ molten zinc. Depending on the mass loss method, the corrosion rate of the samples were measured in the molten zinc at different temperature. The corrosion surface of SiC and stainless steel samples were observed by SEM. The corrosion mechanism was discussed. The experimental results show that the molten zinc corrosion of stainless steel was dominated by dissolvent corrosion. The corrosion rate is much higher than that of SiC. The stainless steel samples were eaten off at 700 ℃ for 8 h, and at 750 ℃ and 800℃ for 5 h. For the permeability silicon SiC sample, the molten zinc corrosion was cooperatively caused by the cracks and spalling, and dissolvent of Si. The corrosion rate of SiC is affected greatly by the temperature. The corrosion rate of SiC is slight when the molten zinc temperature is 750 ℃. The corrosion rate is only 0.6 % at 750℃ for 8 h. However, the dissolvent corrosion of SiC samples occurs obviously when the temperature is higher than 800℃, the corrosion rate quickly increases. The corrosion rate is up to 3 % at 800℃ for 8 h.
出处
《热加工工艺》
CSCD
北大核心
2012年第8期65-67,71,共4页
Hot Working Technology
关键词
液锌腐蚀
碳化硅
腐蚀速度
molten zinc corrosion
SiC
corrosion rate
