Titanium tungsten cermet is a new type of metal ceramic material which was born in 1970s.

 

 

It has many advantages, such as low density, good chemical stability and oxidation resistance, small friction coefficient to steel, hard to cut metal, resistance to cutting, melting and diffusion, and has been greatly developed in recent years.

 

The method of preparing Ti (C, N) and its solid solution powder in industry generally is the ball milling mixture of TiC + WC, TiO₂+WO₃+C or Ti+W+C, and the carbon thermal synthesis reaction is carried out in the range of 1600-2000 degrees centigrade. Recently, some scholars have tried to synthesize Ti (C, N) solid solution and other carbide powder in the laboratory by using "precursor + carbothermal reduction" technology. The method has the advantages of simple process, low preparation cost, low synthesis temperature and easy synthesis of nanometer grade powder.

 

Preparation of nano Ti (C, N) - based cermets by "precursor + carbothermal reduction" process: 1. The raw materials such as ammonium metatungstate, meta-titanic acid, acid and xylose were placed in a beaker containing a certain amount of deionized water and dissolved in a precursor solution, and then placed in an oven and dried at 80 °C to obtain a precursor mixture powder. 2. The precursor mixture was calcined in a tube furnace to obtain TiO₂ + WO₃+B₂O₃ products. 3. The nanocrystalline Ti (W) (B, C, N) powders were successfully prepared by carbothermal reduction and carbothermal reduction nitridation at 1200 °C in a vacuum tube furnace for 2h, and the average grain size of the powder was about 21.3nm.

 

Compared with the ordinary milling heat + traditional carbon "reduction" precursor + carbon thermal reduction method can be synthesized in low temperature to obtain phase components of nanocrystalline powder single, metal ceramic tool not only for a better quality, and the cost savings of 30% compared with ball milling method.

 

Injection molding of cemented carbide belongs to the powder injection molding process (PIM), which is complex and has many influencing factors. Improving and stabilizing the properties of cemented carbide during the PIM process is always the most difficult point in PIM process.

Solvent debinding is widely used in the debinding process of cemented carbide injection molding. Parameters of solvent debinding process have an important impact on the degreasing process and product quality, in which the influence of degreasing temperature is particularly obvious. The temperature not only affects the debinding rate, but also has obvious influence on the bubble, cracking and other defects.

Injection molding technology has been widely used in the field of cemented carbide production as a result of its excellent characteristics. In the field of cemented carbide production, the two-step degreasing process is most commonly used solvent degreasing + thermal debinding. 

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