The Study Of Chemical Coloring And Corrosion Resistance Of Stainless Steel

Colored stainless steel as an excellent corrosion resistance of decorative materials has a wide range of applications in building decoration, kitchenware, appliances, signage printing, art and other fields. Therefore, stainless steel coloring technology has important significance. Colored stainless steel not only has colorful color, but also its corrosion resistance, abrasion resistance, weather resistance is better than ordinary stainless steel. Nearly four decades, domestic research institutions conducted in-depth research in colored stainless steel technology, and made a lot of achievements in recent years, the domestic colored stainless steel companies have also put into operation.Current research on colored stainless steel, are mainly focused on the coloring process; the stainless steel material, and the coloring temperature is still not perfect. In the actual production, different stainless steel contains different elements and ingredients, so the correspondence between the potential difference and color is not consistent, so the research of stainless steel material has significance impact on the color and corrosion resistance of colored stainless steel. The temperature of industrial production is above80℃, not only brings high energy consumption, and the concentration of coloring liquid may change due to evaporation of water, which causes the color reproducibility of colored stainless steel deteriorated. After adding a small amount of rare earth additives, coloring temperature can be significantly reduced, color reproducibility can be improved. Meanwhile, research on rare earths additives has not been reported in detail. This paper studies the impact of stainless steel materials and rare earth additives on coloring process and the corrosion resistance of stainless steel, concrete work as follows:1.H2SO4-CrO3coloring solution is used, INCO method chemical coloring process to201、304、430type stainless steel is conducted at different temperature, and influence of stainless steel material in coloring rate and corrosion resistance are researched through the polarization curves, SEM, EDS analysis. The results show that under the same coloring conditions:the color of three colored stainless steel is not the same;304type stainless steel colored faster than others and has the best corrosion resistance; element content of Cr, Ni can have a great influence on the corrosion resistance of colored stainless steel.2. Chemical coloring of430stainless steel is conducted at70℃, by adding the rare earth cerium nitrate into traditional coloring solution. Polarization curves, SEM analysis are used to research the surface morphology and corrosion resistance of the colored film. The results show that not only can the cerium nitrate significantly improves coloring rate of430stainless steel at a lower temperature, but also improves the film surface roughness and corrosion resistance.3. JSM6510LV scanning electron microscope is used to measure the thickness of yellow and fuchsia colored film formed on430type stainless steel. The thickness of yellow and fuchsia colored film is270nm and298nm separately, which consistent with the literature. This method is simple, accurate and suitable for metal surface coating thickness measurements.