Core materials commonly used in drawing die are hard alloy, diamond, diamond etc.. According to the different processing procedure, is machined by wire material properties, and the quality of wire requirements to choose the core material shall be in the choice of wire drawing die. Reasonable choice of core material, is the main way to prolong its service life.

The following describes the influence of different materials on the mold service life of drawing die

1 cemented carbide

Drawing die hard alloy with low CO content of carbide - cobalt alloys, it has better wear resistance, impact resistance, throwing light and corrosion resistance, easy to repair, low price, is commonly used drawing die core production of materials, widely used in coarse, silk stretch. Study shows that by improving the composition and structure of the hard alloy, controlling the value of the carbon content, the fine carbide particles can improve the performance of the material and prolong its service life. At home and abroad by hot isostatic pressing (hip) processing, ultrafine grained process and adding rare earth elements to reduce the porosity, grain refinement, improve the alloy hardness, reduce friction coefficient; and the use of chemical gas phase deposition (CVD) method and physical vapor deposition (PVD) method on the surface of the hard alloy forming diamond films or titanium nitride coating, increase the surface strength of the alloy.

2 natural diamond

Commonly known as natural diamond diamonds, is the hardest substance in the nature, has a very high wear resistance and thermal conductivity, for tungsten and molybdenum wire tension can improve the surface quality of wire, improve the wire properties and dimensional accuracy, mainly for tensile wire and wire product. But it is very brittle, the impact resistance performance is poor, and the hardness is anisotropic, and it is easy to wear when drawing die. In addition, diamond is rare, expensive, difficult to process, so in the stretch, rough wire is limited.

3 synthetic diamond

Diamond also known as polycrystalline diamond, it is by many single crystal particles without the stereospecific polymerization of multi crystal, with high strength and hardness, impact resistance strong, uniform properties and good comprehensive properties. During drawing, the service life is higher than that of the diamond model and the hard alloy mould, and the size of the wire is stable, and the surface quality is good. But the grain of synthetic polycrystalline diamond thick, polishing difficulties, smooth surface tensile filaments as natural diamond. Through the refinement of grain, can improve the polishing performance, in the wire drawing die to replace natural diamond, greatly reduce costs, improve product quality.