Steel bonded tungsten carbide is a kind of tungsten carbide which is made of steel as binder, carbide as hard phase and made by powder metallurgy method. Hard phases of steel bonded tungsten carbide are TiC and WC, while the bonding phase is divided into high carbon steel, medium alloy tool steel, high chromium tool steel, high speed steel, stainless steel and high manganese steel according to the steel grades.

 

 

On the process, the composition of steel bonded carbide has extensive adjustability. According to the requirement of die and mould, the steel bar as the bonding phase of steel bonded carbide can be changed in a large range. At the same time, the content of the hard phase can also be reduced or increased in the range of 10%-90%, which is conducive to reasonable selection under the premise of meeting the requirements to reduce the cost.

 

When the content of hard phase is 30%-50%, it can be machined after sintering. When the content of hard phase is 65%-70%, these alloys are similar to the ordinary tungsten carbide. Because of its high hardness, it can only be used for grinding or machining. Steel bonded carbide can increase or decrease its hardness by heat treatment. Many varieties of machinable steel bonded tungsten carbide have solderability and forgability.

 

Take the selection of tile mold as an example. One of the key parts of the mould is the liner, which directly participates in the forming of ceramic tiles, and is exposed to powder with great corrosive and frictional resistance. Relative motion of ceramic tile body and liner forming face occurs under high pressure. The working conditions of ceramic tile powder in molding are: 40-600℃, 20-28MPa.

 

It can be seen that the working pressure of the forming surface is very large, and the wear is serious. The liner is easily damaged by the powder wear or the grooves are worn out. The better service life of domestic dies is about 600 thousand times, while the life of similar dies abroad is about 1 million 500 thousand times. In order to change this situation, we must choose the mould material correctly and reasonably.

 

According to a variety of data, the steel bonded hard alloy is used in the ceramic tile mould, and the life span is 10 times higher than that of the general tool steel. The economic effect is very remarkable, and it has a broad prospect. In view of the environment and force condition of the ceramic tile mold lining board, the 40C: material is selected as the matrix and the steel bonded hard alloy liner structure is bonded with a certain thickness. On the one hand, through certain technological means, the strength and toughness of the matrix of 40Cr liner can be greatly improved and its hardness and wear resistance are guaranteed. On the other hand, the proper choice of steel bonded carbide brand and full play of its high wear resistance can greatly improve the service life of the die. According to the working conditions of ceramic tile mould liner, it requires high wear resistance, good strength and toughness, and can be machined. GT35 steel knot cemented carbide can be selected.

 

The unique characteristics of steel bonded cemented carbide make its working time become more than 10 times longer than that of the general alloy tool steel die, thus reducing the amount of die and the time needed to replace the die. At the same time, because it is extremely wear-resistant, the roughness value is small, easy to release, and so on, the edge angle of the green body is very complete, which improves the quality and grade of the product. Because of these outstanding characteristics of steel bonded tungsten carbide die, it is an inevitable trend for it to replace ordinary Cr12 (or Cr12MoV) die.