Galvanized Steel Dezincification
There are different reasons of dezincification of Galvanized Steel during they are stamping. One of ways to improve the dezincification of Galvanized Steel is to improve mould surface treatment (such as: coating treatment, chemical heat treatment, etc.). What is the specific principle of those treatments? Today we shall discuss it in detail.
In fact, not only galvanized Steel which owns galvanized layer will be worn on the surface, but non-galvanized steel sheet exist falling powder. This is normal friction between metal material and mould. There are metal adhesions occurred on some parts of mould. Sometimes this kind of friction shall be resulted in serious injury of the surface of Galvanized Steel.
There is an reference paper confirmed that in the absence of special surface treatment, if the stamping mould is made of simple steel materials, when the forming force is large (forming force proportional to the material strength and parts complexity), regardless of mould quenching hardness higher, the problem of injury cannot be avoided.
To solve this problem, the principle is to change mould’s the nature of friction with usage of buffering material which is not easily falling off or sticky.
The solution of dezincification to specific methods could be:
1.Change the mould surface characteristics: Treatment the surface of the mould. The treatment include: Chrome-Plated on mould or more efficient TD treatment (thermal diffusion-based carbide cladding).
2.Change the surface characteristics of galvanized steel: Treatment the surface of the galvanized steel such as making phosphate film on the electrical galvanized steel, and painting high lubrication on the surface of hot-dipped galvanized steel.
3.Adding buffer layer separately : Adding another layer of material between the mould and the stamping galvanized steel part, so that the work piece and the mould could be physical separation (such as increased lubrication or add a layer of PVC or other materials).
