1. Brass itself oxidizes in the air, so we can provide heating conditions to accelerate oxidation. By heating, the copper in the alloy reacts with oxygen to form black copper oxide, which is black.

2. The blackening treatment on the surface of brass often produces a black surface film on the surface by chemical methods. The blackening process of brass is due to its high production efficiency and good corrosion resistance of the oxide film layer. It has been widely used.

The main purpose of the blackened surface of brass machining parts is matting, decoration and anti-corrosion. In recent years, the black nickel plating process has been adopted by some companies, but the black nickel plating is an anodic coating, and the problem of easy discoloration is a headache.

Brass is an alloy composed of copper and zinc. Brass composed of copper and zinc is called ordinary brass. If it is a variety of alloys composed of more than two elements, it is called special brass. Brass has With strong abrasion resistance, brass is often used to manufacture valves, water pipes, connecting pipes for internal and external air conditioners and radiators.