One of the fastener surface treatment technologies - Dacromet, its Dacromet is the transliteration and abbreviation of DACROMET, referred to as Dacromet, Dacromet, and Dicromet for short. Domestically named zinc-chromium coating, it is a new type of anti-corrosion coating with zinc powder, aluminum powder, chromic acid and deionized water as the main components.
Dacromet has extremely high corrosion resistance. It is a clean production process and a high-tech that is in the germination stage in China. It is known as an epoch-making new process in the international surface treatment industry. This process can replace steel galvanizing, cadmium, zinc-based alloys, hot-dip galvanizing, thermal spray galvanizing, and mechanical galvanizing.
Dacromet for fasteners is a new type of surface treatment technology. Compared with the traditional electroplating process, Dacromet is a "green electroplating". Its advantages are as follows:
1) Super corrosion resistance
2) No hydrogen embrittlement
3) High heat resistance
4) Good adhesion and recoating performance
5) Good permeability
6) No pollution and public hazards
The disadvantages of Dacromet surface treatment technology for fasteners are:
1) Dacromet contains chromium ions that are harmful to the environment and the human body, especially hexavalent chromium ions that are carcinogenic.
2) The sintering temperature of dacromet is high, the time is long, and the energy consumption is large.
3) The surface hardness of dacromet is not high, the wear resistance is not good, and the products coated with dacromet are not suitable for contact and connection with copper, magnesium, nickel and stainless steel parts, because they will cause contact corrosion, Affect the surface quality and anti-corrosion performance of products.
4) The surface color of Dacromet coating is single, only silver white and silver gray, which is not suitable for the individual needs of automobile development.
5) The conductivity of Dacromet coating is not very good, so it is not suitable for conductively connected parts, such as grounding bolts of electrical appliances.