Shenzhen CNC machining will help you understand the surface hardening treatment technology of metal mould. The diffusion method of metal carbide coating technology is to place the workpiece in a special medium and form a layer of metal carbide of several microns to tens of microns on the workpiece surface by diffusion. The carbide layer has extremely high hardness, HV can reach 1600~3000 (depending on the type of carbide). In addition, the carbide coating is metallurgically combined with the matrix, which does not affect the surface finish of the workpiece. It has extremely high wear resistance, anti seizure (bonding), corrosion resistance and other properties, which can greatly improve the service life of tools, dies and mechanical parts.
The method of forming superhard compound film on the surface of the workpiece is an effective and economical method to greatly improve its wear resistance, anti seizure (anti adhesion), corrosion resistance and other properties, so as to greatly improve its service life. At present, the superhardening treatment methods of workpiece surface mainly include physical vapor deposition (PVD), chemical vapor deposition (CVD), physical chemical vapor deposition (PCVD), and diffusion metal carbide coating technology
Among them, PVD method has the advantages of low deposition temperature and small deformation of the workpiece. However, due to the poor adhesion between the film and the substrate, and the poor process wrapping, it is often difficult to play the performance advantages of superhard compound film.
CVD method has outstanding advantages such as good film substrate bonding force and good process wrapping, but for a large number of iron and steel materials, the subsequent matrix hardening treatment is more troublesome, and the film is easy to be damaged with a little carelessness. Therefore, its application mainly focuses on materials such as cemented carbide.
The deposition temperature of PCVD method is low, and the film substrate bonding force and process wrapping property are greatly improved compared with PVD method, but compared with diffusion method, the film substrate bonding force still has a large gap. In addition, because PCVD method is still plasma film forming, although the wrapping property is improved compared with PVD method, it cannot be eliminated.
The metal carbide coating formed by the diffusion method metal carbide coating technology is metallurgically bonded with the matrix, and has a film substrate bonding force unmatched by PVD and PCVD. Therefore, this technology can really give play to the performance advantages of the super hard film. In addition, this technology does not have the problem of coating, and the subsequent matrix hardening treatment is convenient and can be repeated for many times, making the applicability of this technology more extensive.