Abstract
Composite films based on salts such as lanthanum and silica prepared by sol-gel route have been studied to improve the corrosion resistance of magnesium alloy. The surface of the samples was modified under hydrofluoric acid conditions and then coated by different sol films via spinning deposition techniques. Electrochemical impedance spectroscopy and polarisation measurements have been used to evaluate the film corrosion protection performance in 3•5 wt-% neutral NaCl solution. The optimum conditions under which such treatments can provide good corrosion protection to the magnesium alloy substrate were determined. The surface morphology of the treated samples was investigated using SEM. The structure of lanthanum and silica sol was determined by X-ray powder diffraction and Fourier transform infrared spectrum respectively. Results showed that the combination of surface fluoride treatments and silica sol film was found to have a marked effect on the corrosion protection of AZ91D magnesium alloy.
| Original language | English |
|---|---|
| Pages (from-to) | 41-46 |
| Number of pages | 6 |
| Journal | Transactions of the Institute of Metal Finishing |
| Volume | 88 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1 Jan 2010 |
| Externally published | Yes |
Keywords
- Composite films
- Corrosion resistance
- Fluoride layer
- Lanthanum sol
- Silica sol