|
| Comparison Study on Performance of IVD and ILEp Aluminum Coatings |
| Received:November 07, 2016 Revised:May 15, 2017 |
| View Full Text View/Add Comment Download reader |
| DOI：10.7643/ issn.1672-9242.2017.04.017 |
| KeyWord:ion vapor deposition (IVD) electroplating in ionic liquid (ILEp) corrosion resistance hydrogen brittleness contact corrosion resistance |
| Author | Institution |
| ZHAN Zhong-wei |
Aviation Key Laboratory of Science and Technology on advanced Corrosion and Protection for Aviation Material, Beijing Institute of Aeronautical Materials, Surface Engineering Institution, Beijing , China |
| SUN Zhi-hua |
Aviation Key Laboratory of Science and Technology on advanced Corrosion and Protection for Aviation Material, Beijing Institute of Aeronautical Materials, Surface Engineering Institution, Beijing , China |
| TANG Zhi-hui |
Aviation Key Laboratory of Science and Technology on advanced Corrosion and Protection for Aviation Material, Beijing Institute of Aeronautical Materials, Surface Engineering Institution, Beijing , China |
| ZHANG Qi |
Aviation Key Laboratory of Science and Technology on advanced Corrosion and Protection for Aviation Material, Beijing Institute of Aeronautical Materials, Surface Engineering Institution, Beijing , China |
|
| Hits: |
| Download times: |
| Abstract: |
| To have comparative study on performances of IVD and ILE aluminum coatings. Methods In allusion to the requirement of environmental treatment on high-strength steel surface, two aluminum coatings were formulated on 300M steel and studied. The morphology of surface and cross section of the two coatings were characterized by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Atomic force microscope (AFM) was applied to observe the morphology and measure the roughness of the coatings. The contact corrosion was tested between the two aluminum coatings and aluminum alloy. Influences of two coatings on the hydrogen brittleness was evaluated by tensile test of notched bar. The corrosion resistance of the two coatings was tested by neutral salt spray and alternative immersion in artificial seawater. It was also compared with the cadmium plating coating. Electrochemical method was conducted to evaluate the changes of impedance spectroscopy property during the corrosion test. Results Surface topographys of the two coatings were much different. After densifying treatment, the IVD Al coating exhibited uniform round concave pits with roughness of 0.88 μm, which is attributed to shot preening process. The Alep Al coating has a typical morphology of electroplating composing of convex parts, with roughness of 0.71 μm. The two aluminum coatings came into contact with aluminum alloy without little galvanic corrosion risk. The notched bars did not break after a 200 h tensile test, suggesting no hydrogen brittleness was introduced into the substrate. The two aluminum coatings exhibited excellent corrosion resistance. The main indexes including hydrogen brittleness and corrosion resistance were equal to that of cadmium plating. Conclusion These two coatings are uniform and tight, and are free from obvious defects such as porosity and crack. They have galvanic corrosion performance, and won't produce hydrogen embrittlement of 300M steel matrix. Their corrosion resistance is excellent. |
| Close |
|
|
|