Chemical nature of phytic acid conversion coating on AZ61 magnesium alloy |
| |
Authors: | Fusheng Pan Dingfei Zhang |
| |
Institution: | a College of Materials Science and Engineering, Chongqing University, Chongqing, 400044, China b Chemistry Department, the Third Military Medical University, Chongqing, 400038, China |
| |
Abstract: | Phytic acid (PA) conversion coating on AZ61 magnesium alloy was prepared by the method of deposition. The influences of pH, time and PA concentration on the formation process, microstructure and properties of the conversion coating were investigated. Scanning electron microscopy (SEM) was used to observe the microstructure. The chemical nature of conversion coating was investigated by energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques. The corrosion resistance was examined by means of potentiodynamic polarization method. The adhesive ability was tested by score experiments. The results showed that the growth and microstructure of the conversion coatings were all obviously affected by pH, time and PA concentration. In 0.5 mg/ml PA solution with a pH of 5, an optimization conversion coating formed after 20 min immersion time by deposition of PA on AZ61 magnesium alloy surface through chelating with Al3+. It made the corrosion potential Ecorr of sample shifted positively about 171 mV than that of the untreated sample, and the adhesive ability reached to Grade 1 (in accordance with GB/T 9286). |
| |
Keywords: | 68 43 Fg |
本文献已被 ScienceDirect 等数据库收录! |
|