鍍鋅基材於常溫下三價鉻化成膜之研究

• Main Authors: Tsai Yu Te, 蔡郁德
• Other Authors: 葛明德
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/65095607607189926561

碩士 === 國防大學中正理工學院 === 應用化學研究所 === 95 === ABSTRACT The study is aim to develop a trivalent chromium baths, which not only available to conversion at low temperature but also come up to the green process, moreover, has excellent corrosion resistance. Both AC impedance and FE-SEM were certainly showed that chromate conversion at 60℃ has better corrosion resistance than 35℃. The experiment results of XRD, unable to see the peak of ZnO, deduced that the ZnO is the sort of non-crystalline. The chromate conversion rate was enhanced by 0.3 M accelerator at 35℃, so the conversion layers have superior corrosion resistance performance. Nevertheless, the 0.1 M accelerator hasn’t enough to enhance the chromate conversion rate, and therefore the conversion layers have poor performance of corrosion resistance. In the case of 0.5 M accelerator, however, it’s too much to affect the corrosion resistance performance. The chromate conversion process was sufficient to support the formation of conversion layers at 60℃. Hence, adding the accelerator in the trivalent chromium baths, the stresses of conversion layers were formed resulting in the corrosion resistance declined. The NO3--free seems restricted to accelerator’s effect on conversion layers. By means of SIMS, we found that the element A contents (from accelerator) was decreased and the corrosion performance was diminished with the NO3--free. Keywords: trivalent chromium、conversion layer、AC impedance