硫酸羟胺和pH值对低温磷化过程的影响

利用多种方法研究了硫酸羟胺(HAS)和pH值对低温锌系磷化过程的影响,结果表明,HAS是一种非常好的低温磷化促进剂,可以使钢铁材料在低温下生成黑灰色均匀的磷化膜.但是其含量并不是越多越好,而是存在一个峰值.pH值的大小是成膜的一个重要因素,过大或过小均不能成膜;另外pH值对HAS的用量也有影响,pH值大时需要的HAS量多,小时所需量少.

Influence of Hydroxy Amine Sulfate and pH Value on Low Temperature Phosphating of Iron and Steel

The effects of hydroxy amine sulfate(HAS) and pH value on the low-temperature phosphating process of A3 steel were studied using electrochemical method.It was found that HAS as a kind of suitable low-temperature accelerating agent for zinc-based phosphating was beneficial to the formation of a uniform dark gray conversion coating on the surface of the A3 steel;and it was imperative to properly control the desired content of the HAS during the phosphating process so as to ensure the quality of the phosphating coating.Moreover,the pH value of the phosphating solution had significant effect on the formation of the phosphating coating as well.Namely,it would be impossible for the phosphating process to continue if the pH value was too high or too small.At the same time,there existed some kind correlation between the pH value and the content of HAS in the phosphating solution,i.e.,a higher content of HAS was needed at a larger pH value,while a smaller content of HAS was needed at a lower pH value.