The Technology Research Of Plasma Oxidation On Steel

Firstly, illuminate the principle of plasma oxidation and steel surface corrosion, on the basis of these principles, the principle of plasma oxidation on steel in-situ synthesis ceramics coating has been primarily explored. According to this principle, the thought of the experimentation has been designed, decide to choose Al2O3 as ceramics film on steel ,in order to get this material, use the solution mixed with NaAlO2, Na2SiO3,(NaPO3)6 in the process. Then the technological process has been tried. The method of how to in-situ synthesize ceramics coating by plasma oxidation has been found after explored a series of technological process, such as directly plasma oxidation on steel, plasma oxidation on steel after blackening, plasma oxidation on steel after quenching, and so on. Then analyse the advantages and disadvantages of those methods.Finally using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Constant Potential Apparatus , the micro-shape , structure and corrosion resistance of the ceramic coating have been analyzed and explained . The result shows that :By using the solution mixed with NaAlO2, Na2SiO3 and(NaPO3)6 , steel can discharge in this solution and the ceramic layer can be produced .On the surface of layer there are a lot of micropores by electric discharge just like"volcano deposit".With the process going, the number of the micropore is increasing. The coating was mainly composed of O, Al, Si and P. These chemical elements form a noncrystalline layer, which has a good corrosion resistance .The corrosion resistance of steel plasma oxidation coating was also well improved .