直流等离子渗氮法对纯铝耐腐性的改善--时间和温度的影响

The effect of time and temperature in increasing the corrosion resistance of pure aluminum by DC plasma nitriding

为了提高铝的耐腐蚀性能,在氮氢混合物(PN2/PH2=4/1)等离子体中用直流等离子体渗氮法对铝进行了处理。处理温度为673K和723K,处理时间为8h、12h和20h。通过利用扫描电子显微镜(SEM)、X射线能量色散光谱仪(EDX)以及X射线衍射仪进行的表面分析发现,随着处理时间的延长和处理温度的升高,样品表面生成层的生长速度增加。为了考察样品的耐腐蚀性,在质量浓度为3.5%的氯化钠溶液中进行了电化学动态极化实验,结果显示,样品的腐蚀行为取决于生成AlN的质量。当处理温度为723K、处理时间为20h时,试样的耐腐蚀性最好。

In order to increase the corrosion resistance of aluminum,this study used DC plasma nitriding in the mixture of（PN2/PH2 = 4/1） plasma at the temperature of 673 K and 723 K for 8,12 and 20 hours.After some surface analyses such as SEM,EDX and XRD,it was found that the growth of the created layer on the surface of samples increased with treatment time and temperature.For investigating the corrosion resistance of sample,this study used potentiodynamic polarization test in 3.5% NaCl solution.The result showed that the corrosion behavior of samples depended on the quality of AlN layer,and the highest corrosion resistance achieved at 723 K and 20 hours.