Preparation of the high corrosion resistant and anti-black patina chromate solution and its film on hot dip galvanized steel

摘要

In the present invention, the white rust generation time is secured over 240 hours on the basis of SST at 50 ° C to 60 ° C, which is the drying temperature of the coated chromate treatment of the hot dip galvanizing facility. The present invention relates to a chromate solution having high corrosion resistance and high blackening resistance, and a chromate coating method using the same.;In the case of conventional hot dip galvanized chromate solution, it is known that the corrosion resistance blackening resistance increases as the drying temperature is higher, but it is difficult to secure a high drying temperature in actual facilities. Therefore, the subject of the present invention is to develop a high corrosion resistant high blackening chromate solution and a chromate film prepared using this solution, which can ensure corrosion resistance blackening resistance even at low chromate drying temperature.