Common Surface Treatments For Bolts

Coating: applying a coating to the surface of the bolt to create a uniform film that improves its corrosion resistance and appearance. The advantage is that it looks good, but the disadvantage is that it is not durable and is easily scratched.
Hot-dip galvanizing: immersing the bolt in molten zinc to improve its corrosion resistance. The advantage is that it has strong anti-corrosion ability and is not easy to fall off, but the disadvantage is that the surface is not beautiful enough.
Electroplating: immersing the bolt in an electrolyte and depositing a layer of metal on the surface of the bolt through electrolysis to improve its corrosion resistance and appearance. The advantage is that the surface is smooth and beautiful, but the disadvantage is that it is prone to hydrogen embrittlement.
Dacro: immersing the bolts into a zinc-aluminum solution, ensuring that the bolt is fully in contact with the solution before shaking off the excess solution and drying it. Repeat the above process 2-4 times to form a dense film on the surface of the bolt, achieving the effect of anticorrosion. The advantage of this process is that the surface is beautiful and not easy to fall off, but the disadvantage is that it is not durable and is easily scratched. Now there is a hexavalent chromium-free formula, which is more environmentally friendly.