Tungsten carbide (WC) is one of the hardest materials used in modern industry. Producing WC products requires several key industrial processes: powder mixing, wet grinding, spray drying, pressing, sintering, and quality inspection. During sintering, the volume of the cemented carbide shrinks by about half. This article explains what happens during the tungsten carbide sintering process.

The temperature is gradually increased to below 1800°C. Moisture, gases, and residual solvents in the compact gradually evaporate. Binder decomposition increases the carbon content of the sintered body, with variations depending on sintering conditions. Meanwhile, contact stress between powder particles is gradually eliminated as the temperature rises.

The temperature continues to rise slowly into the solid-phase range (1800°C to the eutectic temperature). The eutectic temperature is the lowest temperature at which liquid phase first appears in the system. In this stage, plastic flow increases, the sintered body shrinks significantly, and the tungsten carbide volume decreases noticeably.

When the temperature reaches the process peak (sintering temperature), the liquid phase appears and shrinkage is rapidly completed. Under the influence of liquid surface tension, powder particles move closer together and internal pores are filled by the liquid phase.

After sintering, the cemented carbide cools with the furnace to room temperature. Some factories recover energy from the sintering furnace's residual heat. As the temperature decreases, the alloy's final microstructure becomes fixed.

Sintering is an extremely precise process requiring careful parameter control at each stage. If you're interested in tungsten carbide products, please contact us via the phone number or email on the left side of the page, or send us a message using the form at the bottom for more details.