Views: 2 Author: Site Editor Publish Time: 2023-04-14 Origin: Site
Dacros technology is the latest surface treatment technology, and its zinc chromium coating is known as an epoch-making revolutionary product in the international surface treatment industry. Dacrol coating has the advantages of high corrosion resistance (7-10 times that of galvanizing), high heat resistance (250℃ can continue to be used normally), no hydrogen embrittleness, high permeability, good weather resistance, good adhesion with matrix, no pollution to the environment and so on.
Advantages of Dacros technology:
Zinc-chromium coating (Dacrol) has the following significant advantages over traditional electrogalvanizing, cadmium electroplating and hot dip galvanizing.
(1) Strong candle corrosion resistance. Zinc chrome coating (Dacrol) of the same thickness as other coatings (plating)
The candle resistance is better than any other coating. When the thickness is 8μm, the neutral salt spray test can reach 1000 ~ 2000 hours, which is impossible for electrofered zinc.
(2) No oxygen embrittlement is produced. Hydrogen embrittlement is a defect that can not be completely overcome by the traditional galvanizing process. When coating broken chromium coating, because there is no acid pickling, there is no oxygen infiltration during the electric transfer, and it is cured at a high temperature, the zinc chromium coating has absolutely no oxygen embrittlement phenomenon, especially for the anti-corrosion treatment of high strength parts.
(3) High permeability. The metal parts coated by the collature coating can also form a coating with good anti-corrosion performance in the fine gap, which is conducive to the surface treatment of complex parts.
(4) Good weather resistance. Zinc chromium coating can withstand sulfur dioxide, acid rain, smoke, dust immersion candle. Its sulfur dioxide resistance test can reach 3 cycles. In addition, it has the advantages of corrosion resistance to chemicals, gasoline and oil.
(5) Good coating performance. The test shows that the coating surface of zinc collate coating has a strong adhesion to paint and coatings, so it can be re-coated on the surface of broken chromium coating to form the required film of various colors.
(6) Good heat resistance. Zinc-chromium coating still has good corrosion resistance at higher temperature (≤300℃), and can be used for parts with certain heat resistance requirements.
(7) High adhesion. After curing at certain temperature, the zinc-Cr coating has better bonding force with steel matrix than galvanizing.
(8) No pollution to the environment, no rot to equipment, no damage to the human body.
Problems with Dacros technology
(1) The ordinary zinc chromium coating is a kind of silver gray non-decorative coating, the surface roughness is high, it is easy to adhere to dirt in the process of storage and handling, affecting the appearance.
(2) Because the main component of zinc chromium coating is the essence, and the hardness of elemental catalpa is only about HV80, resulting in the overall hardness of front chromium coating is low, resulting in no wear resistance.
(3) Although the chromium coating is a conductor, but poor conductor, therefore, the higher requirements for electrical conductivity of the kit is not necessarily applicable.
(4) Energy consumption. Because the sintering temperature of Dacrossum is as high as 300℃, the process of curing equipment consumes a lot of energy and costs a lot. The cost consumed has accounted for 1/4 of the total cost.
1. Dacrol will age rapidly when exposed to light, so the coating process of Dacrol should be done indoors.
2. Too low or too high baking temperature will cause the loss of anti-corrosion ability of dacrosol. Dacrosol should be baked in an appropriate temperature range.
3. Dacrol has a short life cycle, so use it as soon as possible.
4. The wear resistance of dacrol is poor, so it should be top coated with Dacrol, and then coated with other coatings with wear resistance.