Dacromet coating, in the forming process of metal surface, the volatile material is almost all the water through the gasification,and no pollution, has been widely used in industrial developed countries, is gradually replacing the serious pollution of electroplating zinc, chromium, hot dip galvanizing, hot spray zinc, mechanical galvanizing, zinc-based alloy coating, oxidation, phosphating and other traditional surface treatment processes,fundamentally reduce the occurrence of environmental pollution, and has the advantages and characteristics incomparable to other surface treatments.