The four basic stages of tungsten steel sintering process:
1. Remove the forming agent and the pre-firing stage. In this stage, the sintered body changes as follows:
The removal of molding agent, sintering initial stage with the rise of temperature, molding agent gradually decomposition or vaporization, eliminate the sintering body, at the same time, molding agent more or less to the sintering body carburization, carburization amount will change with the type of molding agent, the number and sintering process is different.
The oxides on the surface of the powder are reduced. At the sintering temperature, hydrogen can reduce the oxides of cobalt and tungsten. However, when the molding agent is removed in vacuum and sintering, the reaction between carbon and oxygen is not strong.
The contact stress between the powder particles was gradually eliminated, the bonding metal powder began to recover and recrystallize, surface diffusion began to occur, and the strength of the compaction increased.

2. Solid phase sintering stage (800℃ -- eutectic temperature)
At the temperature before the appearance of liquid phase, in addition to continuing the process of the last stage, the solid reaction and diffusion are intensified, the plastic flow is enhanced, and the sintered body appears obvious shrinkage.

3. Liquid phase sintering stage (eutectic temperature -- sintering temperature)
When the sintered body appears in the liquid phase, the shrinkage is completed quickly, followed by the crystallization transformation, forming the basic microstructure and structure of the alloy.

4. Cooling stage (sintering temperature -- room temperature)
At this stage, the structure and phase composition of tungsten steel change with the different cooling conditions. This characteristic can be used to heat treatment of tungsten steel to improve its physical and mechanical properties.

Application is introduced
Tungsten steel belongs to hard alloy, also known as tungsten titanium alloy.
Hardness can reach 89~95HRA, because of this, tungsten steel products (commonly known as tungsten steel watches), is not easy to be worn, hard and not afraid of annealing, but the quality of brittle characteristics.
The main components of cemented carbide are tungsten carbide and cobalt, which account for 99% of all components, 1% for other metals, so it is also known as tungsten steel.
It is often used in high precision machining, high precision tool materials, lathes, impact drilling bits, glass cutter heads, ceramic tile cutters, hard and brittle.
They are among the rare metals.
Tungsten steel (hard alloy) has a series of excellent properties such as high hardness, wear resistance, good strength and toughness, heat resistance, corrosion resistance, especially its high hardness and wear resistance, even at the temperature of 500℃ is basically unchanged, at 1000℃ still has a very high hardness.
Hard alloy is widely used as materials, such as turning tools, milling cutters, planer cutters, drill bits, boring cutters, etc., for cutting cast iron, nonferrous metals, plastics, chemical fiber, graphite, glass, stone and ordinary steel, also can be used for cutting heat-resistant steel, stainless steel, high manganese steel, tool steel and other difficult to machining materials.
The cutting speed of the new cemented carbide is hundreds of times that of carbon steel.
Tungsten steel (hard alloy) can also be used to make rock drilling tools, mining tools, drilling tools, measuring tools, wear-resistant parts, metal grinding tools, cylinder lining, precision bearings, nozzles, etc.
Tungsten steel, hard alloy mold, plate, bar, square bar, ring, top hammer, roller ring, cutting tools, and a variety of tungsten steel carbide standard specifications large inventory spot.