Black surface treatment of screws
In addition to the blackening and black screw phosphating treatment of steel, the surface treatment of screws also has blackening and black phosphating, letting the screw manufacturer introduce it to everyone. Blackening: it is a common means of metal heat treatment. The principle is to produce a layer of oxide film on the metal surface to isolate the air and achieve the purpose of anti-rust.When the appearance requirement is not high, can use black processing, the surface of steel parts blackening treatment, also have been called hair blue.Bluing is a kind of chemical surface treatment, its main function is formed in the surface layer of dense oxide film, prevent the workpiece on the corrosion rust, improve the wear resistance, it is a kind of surface treatment, not for any impact on the internal organization, it is not heat treatment, quenching and a fundamental difference between the two. Black screw phosphating: a process in which chemical and electrochemical...