Tungsten heavy alloys have also become high-density tungsten alloys. Due to their superior physical and chemical properties, they have become important manufacturing materials, fragmentation materials and radiation protection materials, and are widely used in various fields such as lighting, aerospace, automotive industry, nuclear industry,petrochemical, glass ceramics and metallurgical manufacturing.Strictly controlling the production process of tungsten heavy alloys has a crucial impact on the strength, brittleness, impact toughness, hardness and corrosion resistance of the product. Its production process mainly includes the following steps:
1. Material mixing
According to the composition requirements of the final prepared high-density tungsten alloy, a variety of pre-prepared metal powders to be mixed are put into the inclined mixer at the same time and fully and uniformly stirred for six to eight hours to obtain fully mixed powders.
2. Cold isostatic pressing
Using the conventional cold isostatic pressing process, the mixed powder obtained after thorough mixing is subjected to cold isostatic pressing, the pressure is generally 120-170Mpa, and the time is 1-6min (preferably 2min).
3. High temperature sintering
The pressed body is placed in a high-temperature sintering furnace (pressurized sintering furnace), and sintered under the protection of ammonia decomposition gas or hydrogen to obtain a tungsten alloy sintered body with uniform composition. The sintering temperature is usually 1400-1600 ° C, and the sintering temperature is maintained The time is 30-90min.
4. Quenching
The prepared tungsten alloy sintered billet is placed in a high temperature quenching furnace for continuous quenching treatment. The first-stage quenching temperature is 1100-1500°C, the holding time is 10-50min, the second-stage quenching temperature is 25-80°C, and the holding time is 25-80°C. 30- 40min.
5. Vacuum Annealing
Put the hardened tungsten alloy sintered blank into a high temperature vacuum furnace for vacuum annealing. The vacuum temperature of the high temperature vacuum furnace is not lower than ICT1Pa, the annealing temperature is 1100-1300℃, and the annealing time is 1-4h (the best time is 2h).
