Differences between Dacromet and hot-dip galvanizing process
Dacromet process is baked at around 500F after application, whereas hot-dip galvanizing process is done at the temperature of molten zinc (780F) or hotter. With the latter, you may get some stress relief of the parts that may be a problem for you.Hot dipped galvanising has been around for a long time and is best known. The part is dipped into a molten zinc mixture at a temperature of about 460 ℃ which reacts with carbon dioxide to form zinc carbonate.Dacromet has excellent heat resistance; the conventional galvanized coating will show tiny cracks at higher than 70 ℃, and discolor and its corrosion resistance will be greatly reduced at 200-300 ℃.The curing temperature of Dacromet anti-corrosion film is 300 ℃, so the surface metal will not change its appearance and can still maintain its strong heat-resistant corrosion even if placed at high temperature for a long time.Unlike hot-dip galvanized coating, Dacromet coating has no hydrogen embrittlement. The metal parts treated with Dacromet can form the film even in the finest voids and the anti-corrosion coating with deep permeability. Uniform coating is also applied inside the tubular parts and has good permeability because the Dacromet solution is water-soluble.
Advantages of Dacromet coating
1. Superior corrosion resistance. The thickness of Dacromet film layer is only 4-8μm, but its anti-rust effect is more than 7-10 times of traditional electro-galvanizing, hot-dip galvanizing or coating method. No red rust will occur in the standard parts and pipe joints treated with Dacromet process by salt spray test for more than 1,200h.
2. No hydrogen embrittlement. The Dacromet treatment process determines that there is no hydrogen embrittlement in Dacromet, so Dacromet is ideal for the coating of stressed parts.
3. High heat resistance. Dacromet can resist high temperature corrosion, and the heat-resistant temperature can reach more than 300 ℃. However, peeling or scrapping will occur fin the traditional galvanizing process when the temperature reaches 100 ℃.
4. Good adhesion and recoatability. Dacromet coating has perfect adhesion with the metal substrate and other additional coatings. It’s easy for the treated parts to spray coloring, and the adhesion with the organic coating is even stronger than the phosphate film.
5. Excellent permeability. Due to the electrostatic shielding effect, it is difficult to electroplate the deep holes and slits of the workpiece and the inner wall of the tube, so the above parts of the workpiece cannot be protected by electroplating. Dacromet can enter these parts of the workpiece to form a Dacromet coating.
6. No pollution and public hazards. Dacromet does not produce waste water or waste gas that pollutes the environment during the whole process of production, processing and coating of workpieces, so there is no need for three waste treatment, thus reducing the treatment cost.
7. Longer salt spray hours. More than 500 salt spray hours compared to a maximum of 240 hours on zinc galvanized coating. Salt spray is am industry standard test where the parts are placed at a controlled temperature of 35 ℃ and subjected to a continuous spray of sodium-chloride solution. The salt spray test is recorded in hours and is complete when red rust appears on the parts.
Seven benefits of Junhe Dacromet coating solution
Formulated with high quality raw materials, Junhe Dacromet coating solution is an alternative to electro-galvanizing and hot-dip galvanizing for surface corrosion protection. A series of products of Junhe can meet the requirements of customers at different levels of processing.1. Cost effective. The overall cost of the Junhe coating solution is lower.2. Excellent suspension. The coating solution is uniform and not easy to settle due to good suspension, and the tank solution can be circulated for a long period, which is more convenient for customers with insufficient capacity or intermittent processing.3. Good leveling. The surface is less prone to sagging and orange peel.4. Excellent adhesion. The coating is less likely to peel off and has a stronger corrosion resistance.5. Good dispersion. Due to good dispersion, the surface is uniform and particle-free after surface coating.6. Good surface hardness. Strong scratch resistance, and it’s not easy to bruise during the storage and transportation.7. Good salt spray resistance.The adhesion of Junhe Dacromet coating solution is 50% higher than the products from the competitors.