In metal pressure processing, the tool that forces the metal through the mold under the action of external force, compresses the metal cross-sectional area, and obtains the required cross-sectional area shape and size is called a drawing die. The drawing die is a manufacturer of various metal wires. A very important consumable mold for drawing wire rods. Wire drawing dies have a very wide range of applications. Metal drawing is one of the most common processing techniques for metal materials and plays an important role in the production of various wire and cable products such as the wire and cable industry.

 Material of drawing die

According to the type of material, wire drawing dies can be divided into alloy steel dies, cemented carbide dies, natural diamond dies, polycrystalline diamond wire drawing dies, CVD diamond wire drawing dies and ceramic wire drawing dies. In recent years, the development of new materials has been great. It enriches the application scope of the wire drawing die and improves the service life of the wire drawing die.

Although wire drawing dies can be used to process various metals and alloy materials such as steel, copper, tungsten, and molybdenum, wire drawing dies of different materials have their own applicable processing ranges. The wear patterns and uses of wire drawing dies of different materials when processing the same wire rod There is a big difference in service life, so the wire drawing die material should be selected reasonably to obtain the maximum economic benefits.

Application industries of wire drawing die:

Wire drawing dies are a very important consumable product for wire drawing by various metal wire manufacturers. The application scope of the wire drawing die is very wide. It is mainly used for drawing linear difficult-to-process objects such as bars, wires, wires, and pipes. It is generally suitable for drawing processing operations of metals and alloy materials such as steel, copper, tungsten, and molybdenum. . Since the cost of the wire drawing die can reach more than 1/2 of the wire drawing cost, how to reduce the consumption cost of the wire drawing die and increase its service life is the primary issue that metal wire production units urgently need to solve.

Wire drawing dies are widely used, such as high-precision wire materials used in electronic devices, radars, televisions, instruments and aerospace, as well as commonly used tungsten wires, molybdenum wires, stainless steel wires, wires and cables and various alloy wires, all made of diamond. Drawn from a wire drawing die, the diamond wire drawing die mainly uses natural diamond as raw material, so it has extremely strong wear resistance and a very long service life.

Types of drawing dies

Steel mold

When pulling soft metals (such as gold and silver), a steel mold is sufficient, and the steel mold can have multiple holes of different diameters.

Carbide mold

To draw steel wire (steel wire), a carbide mold is generally used. The typical structure of this mold is: a cylindrical (or slightly tapered) carbide mold core tightly embedded in a circular steel case (case) In the inner hole of the mold core, there are bell radius, entry angel, approach angle, bearing and back relief.

Wire mold

To draw non-ferrous metal wires, such as copper and aluminum, drawing dies similar to steel wire dies are often used, and the inner hole shapes are somewhat different.

4. Polycrystalline mold

Polycrystalline dies (artificial diamonds) can be used to draw thin wires, and wire drawing dies using natural diamonds can be used.

 Purpose of wire drawing mold

Wire drawing dies are widely used, such as: high-precision wire materials used in electronic devices, radar, television, instruments and aerospace, as well as commonly used tungsten wire, molybdenum wire, stainless steel wire, wire and cable wire and various alloy wires, all of which use diamond Drawn by drawing die. The diamond wire drawing die uses natural diamond as raw material, so it has strong wear resistance and extremely long service life.

Material of drawing die

After decades of development, many new wire drawing die materials have emerged.

According to the type of material, wire drawing dies can be divided into: alloy steel dies, carbide dies, natural diamond dies, polycrystalline diamond dies, CVD diamond dies and ceramic dies.

In recent years, the development of new materials has greatly enriched the application range of wire drawing dies and increased the service life of wire drawing dies.

 Alloy steel wire drawing die

Alloy steel dies were the early manufacturing materials for wire drawing dies. The materials used to make alloy steel molds are mainly carbon tool steel and alloy tool steel. However, due to the poor hardness, wear resistance and short life of alloy steel molds, they cannot meet the needs of modern production. Therefore, alloy steel molds were quickly eliminated. In current production and processing, alloy steel molds are almost invisible.

 Carbide wire drawing die

Carbide molds are made of carbide. Cemented carbide is a tungsten-cobalt alloy whose main components are tungsten carbide and cobalt.

Tungsten carbide is the "skeleton" of the alloy, which mainly plays a hard and wear-resistant role; cobalt is the bonding metal and is the source of the alloy's toughness. Therefore, compared with alloy steel molds, cemented carbide molds have the following characteristics: high wear resistance, good polishability, low adhesion, small friction coefficient, low energy consumption, and high corrosion resistance. These characteristics make cemented carbide molds Wire drawing dies have a wide range of processing adaptability and have become the most commonly used wire drawing dies today.

Natural diamond wire drawing die

Natural diamond is an allotrope of carbon, and molds made with it have the characteristics of high hardness and good wear resistance. However, natural diamond is relatively brittle and difficult to process. It is generally used to manufacture wire drawing dies with a diameter of less than 1.2mm. In addition, natural diamond is expensive and in short supply. Therefore, natural diamond molds are not the economical and practical wire drawing tool that people ultimately seek.

Polycrystalline diamond wire drawing die

Polycrystalline diamond is made of carefully selected high-quality artificial diamond single crystals plus a small amount of silicon, titanium and other binding agents, and is polymerized under high temperature and high pressure conditions.

Polycrystalline diamond has high hardness and good wear resistance. Compared with other materials, it has its own unique advantages: due to the anisotropy of natural diamond, during the drawing process, when the entire hole is surrounded by When in working condition, natural diamond will wear preferentially at a certain position of the hole; while polycrystalline diamond is polycrystalline and has isotropic characteristics, thus avoiding uneven wear and out-of-round die holes. .

Compared with cemented carbide, the tensile strength of polycrystalline diamond is only 70% of commonly used cemented carbide, but it is 250% harder than cemented carbide. In this way, polycrystalline diamond molds have more advantages than cemented carbide molds. . The wire drawing die made of polycrystalline diamond has good wear resistance, uniform inner hole wear, strong impact resistance, high wire drawing efficiency, and is much cheaper than natural diamond. Therefore, polycrystalline diamond dies are currently widely used in the wire drawing industry.

 CVD wire drawing die

CVD (Chemical Vapor Deposition) coating wire drawing die is a newly developed new technology. Its main method is to coat the carbide wire drawing die with a diamond film.

Diamond film is a pure diamond polycrystal. It has the smoothness and temperature resistance of single crystal diamond, as well as the wear resistance and low price of polycrystalline diamond. It has made great achievements in replacing rare natural diamond in preparing wire drawing die tools. Its widespread use will bring new vitality to the wire drawing die industry.