Do You Know The Sintering Process Of Tungsten Steel Parts

1, Burn-in

In simple terms, the changes that occur in the removal of the molding agent and the sintered body during the calcination stage are:

Removal of the molding agent. As the temperature rises in the early stage of sintering, the molding agent gradually decomposes or vaporizes to exclude the sintered body. At the same time, the molding agent adds more or less carbon to the sintered body. The type, quantity and sintering process vary.

The oxide on the powder surface is reduced. At the sintering temperature, hydrogen can reduce the oxides of cobalt and tungsten. If the molding agent is removed in vacuum and sintered, the carbon-oxygen reaction is not strong. The contact stress between the powder particles is gradually eliminated, the bonding metal powder begins to recover and recrystallize, surface diffusion begins to occur, and the compact strength is improved.

2.Solid-phase sintering

In general, the temperature required for the solid phase sintering stage is 800 ° C-eutectic temperature. At the temperature before the liquid phase appeared, in addition to continuing the process that took place in the previous stage, the solid phase reaction and diffusion intensified, the plastic flow was enhanced, and the sintered body appeared obvious shrinkage.

3.Liquid phase sintering

In general, the temperature required for the liquid phase sintering stage is 800 ° C-the eutectic temperature is also the sintering temperature.

When the liquid phase of the sintered body appears, the shrinkage is completed quickly, followed by crystalline transformation, forming the basic structure and structure of the alloy.

4.Cooling

There is not much requirement for cooling, just room temperature.

At this stage, the structure and phase composition of tungsten steel parts change with cooling conditions. This feature can be used to heat-treat tungsten steel parts to improve their physical and mechanical properties.