Posted by: hannahgwendolyn at 09:53 AM | No Comments | Add Comment
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Wear is a variety of mechanical parts in the working process of one of the main failure forms. Statistics show that in the failure of mechanical parts, about 75% ~ 80% belongs to metal wear, provide machine is about 30% ~ 40% of energy consumption on the friction and wear in the process, and most of the failure phenomena occurred in the material surface, and take various means to improve the surface performance of materials, to enhance the safety and reliability of the parts or to extend the service life is very effective. Cemented carbide as a set of high hardness and toughness is higher than the one of a material, industry often apply it to require the surface damage resistance and abrasion resistance of high places, however The whole of the workpiece using hard alloy will greatly increase the cost, and the requirements of higher than its hardness of the tool, limiting its range of application.

If we can, therefore, in the preparation of low carbon steel surface layer of the cheap kind of tungsten carbide spray coating, make its have the cemented carbide surface performance, in order to improve the service life of the under some special conditions, can reduce the cost, and will be of great technical value and economic significance and broad application prospects. The preparation and properties of WC cemented carbide coating is cemented carbide and hot hardness is the highest, and Co, N I, Fe of metals such as good wettability, especially cobalt. When the temperature rises to more than metal melting, WC can dissolve in the metallic melts.

Introduction arc spraying is a process in which molten metal wire is atomized by high-speed air stream and sprayed onto the surface of workpiece to form a coating by using arc as heat source. Powder composite arc spraying technology is developed on the basis of arc spraying. It is a process of melting wires by arc and adding alloy ceramic powder to the metal surface at high speed to obtain the composite tungsten carbide spray coating with high wear resistance and corrosion resistance. This method can be used for the parts and components made of carbon steel, alloy steel, cast iron, etc. The method can also be used for surface repair of some worn parts or corroded parts. In recent years, arc spraying technology develops rapidly and is widely used in various fields of industry. In this paper, the microstructure of powder composite arc spraying coating and common arc spraying coating are analyzed, the microhardness of coating and substrate are tested, and the wear resistance of the two coatings is compared.

Related link:

http://www.wococarbide.com/Transaction/en_information.html

Posted by: hannahgwendolyn at 09:40 AM | No Comments | Add Comment
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Ultrasonic machining diamond die has long been used in the domestic application, but used in the hard alloy drawing die processing at present few, especially the larger aperture drawing die is so. Ultrasonic grinding is the transformation of electrical energy into mechanical energy at a frequency of about 20,000 cycles per second (20,000 times per second for longitudinal movement); Speed movement processing equipment. At present, complicated softbank welding device is used in the connection of copying needle and changing pole, otherwise the processing efficiency will be greatly reduced. Due to the processing speed, if the cemented carbide drawing die processing, according to the requirements of process strictly every processing a wire-drawing die need to replace a needle, the atmosphere day frequently change requires a lot of needle, the needle and complex welding must be conducted, it is seriously hampering the this technology in the application oftungsten carbide wire drawing dies to touch. In addition, because the processing speed is fast, difficult to master, not easy to achieve linear processing, and high concentration of energy and other factors, therefore, in the promotion and use is also limited.

Compared with hard alloy die, polycrystalline diamond die drawing die has the following obvious advantages:

1. High drawing efficiency

In the process of using the drawing die, necessary maintenance is very important to the service life of the drawing die and the surface quality of wires. It is usually recommended that customers maintain the polycrystalline diamond drawing die every 24 hours. Within 24 hours, the diameter change of polycrystalline diamond wire drawing die is small, and the rate of wire diameter change of pulled wire is also small. For the whole production process, the compression rate of wire diameter of each drawing die is relatively stable, and the ratio of input and output is large.

2. Good wear resistance and long service life

The drawing die life of polycrystalline diamond is about 30-50 times that of the hard alloy die, so it is not necessary to stop the machine often to replace the die in the drawing process. The aperture of polycrystallinetungsten carbidewire drawing dieschanges very little in unit time, and the size of wire pulled out changes very little, which is very beneficial to the winding of reel wire. Generally, the winding number of wires pulled out is fixed. If the finished size of wires becomes larger soon, the winding number will decrease relatively quickly, which requires constant changes in the size of the reel, which is not conducive to the improvement of production efficiency.

Save on raw materials

If the wire coated with metal on the drawing surface is stopped during the drawing process, the electroplating process does not stop, which will lead to the excessive plating thickness of the wire surface that is being electroplated, and the wire shall be cut off when the drawing starts again, resulting in great waste. The more times the machine stops, the greater the waste will be. Using polycrystalline diamond mold, this waste can be greatly reduced.

Posted by: hannahgwendolyn at 09:36 AM | No Comments | Add Comment
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