Overview of some common materials of drawing die

Has experienced several decades of development, there have been a lot of new wire drawing die material. According to the type of material, the drawing die is divided into a variety of alloy die steel, hard alloy die, natural diamond die, polycrystalline diamond die, CVD diamond mould and ceramic mold. In recent years, the development of new materials has greatly enriched the application of drawing die and improve the service life of the wire drawing die.

(1) alloy steel die is an early drawing die manufacturing material. The materials used for the manufacture of alloy steel are carbon tool steel and alloy tool steel. But because the hardness and wear resistance of the alloy steel die is poor, the service life is short, can not meet the needs of modern production, so the alloy steel die soon be eliminated, in the current production and processing has almost see the alloy steel die.

(2) hard alloy mould is made of hard alloy. Cemented carbide is a kind of tungsten cobalt alloy, its main component is tungsten carbide and cobalt. Tungsten carbide is the "skeleton" of the alloy, mainly from the hard and wear-resistant role; cobalt is the bond of metal, is the source of alloy toughness. Therefore, hard alloy die and alloy steel die compared with the following characteristics: high wear resistance, good polishing, adhesion, friction coefficient is small, energy consumption is low, and the corrosion resistance of high. These characteristics make carbide drawing die has a wide range of processing adaptability, become today's most widely used wire drawing die.

(3) natural diamond are allotropes of carbon, with the mold making it has the characteristics of high hardness and good wear resistance etc.. But the natural diamond is more brittle and difficult to process, and is generally used to make the drawing die with the diameter below 1.2mm. In addition, natural diamond prices are expensive, supply shortage, so the natural diamond model is not the end of the people seeking the economic and practical drawing tool.

(4) polycrystalline diamond is used after carefully selected high quality synthetic diamond single crystal with a small amount of silicon and titanium bond, under the conditions of high temperature and high pressure polymerization. Polycrystalline diamond of high hardness and good wear resistance, compared with other materials, it has its own unique advantages: due to the anisotropy of natural diamond, in the drawing process, when around the hole in the working state, natural diamond in the hole of a position will occur preferentially wear; and polycrystalline diamond belongs to multi crystal, has isotropic characteristics, thus avoiding the die hole wear is not uniform and the die hole Buyuan phenomenon. Compared with the hard alloy, the tensile strength of polycrystalline diamond is only 70% of the common hard alloy, but than hard alloy hard 250% so that the polycrystalline diamond die has more advantage than the hard alloy die. Made of polycrystalline diamond drawing die wear resistance, abrasion of the inner hole of the uniform, strong impact resistance, high efficiency of drawing, and the price than the natural diamond much cheaper. The polycrystalline diamond wire drawing die in the wire drawing industry applications.

5) CVD (chemical vapor deposition) it not only has the single crystal diamond is bright and clean degree, temperature resistance, but also has the advantages of polycrystalline diamond wear resistance and low price, achieved good results in instead of rare natural diamond by drawing die tool and its widespread use for drawing die industry to bring new vitality.

(6) high performance ceramic materials have the characteristics of high hardness, good wear resistance, high chemical stability, excellent mechanical properties at high temperature and not easy to bond with the metal, which can be widely used in the processing of difficult materials. Nearly 30 years, due to the ceramic material manufacturing process to achieve the effective control of raw material purity and grain size developed the addition of various carbides, nitrides, borides and oxides, whiskers or a small amount of metal technology. The strength, toughness and impact resistance of ceramic materials have been greatly improved by using many kinds of toughening and reinforcing mechanism.

(7) coated drawing die is a newly developed technology. The main method is to coat metal film on hard alloy wire drawing die. Metal film is a pure titanium coating, it has a good finish, temperature resistance, and has the advantages of titanium and low cost of wear and other advantages, in place of hard alloy wire drawing die tools to achieve good results.