The sintering process of press-briquetting molybdenum powder is an important process technology in the production process of molybdenum powder materials. The purpose of this process is to remove oxygen, improve the activity of molybdenum powder, and reduce the product sintering temperature. In order to achieve the above purposes, by applying pressure and heat, a product with a high degree of metallurgical bonding can be obtained.
Press-briquetting molybdenum powder sintering mainly includes cold isostatic pressing, hot isostatic pressing and uniaxial pressing. Cold isostatic pressing is a general cold forming method. At the same time, it obtains the agglomeration by applying pressure uniformly in all directions. It is mainly used for sintering the molybdenum powder which has small particles, low oxygen content and small hardness. A certain pressure and step time are required before the sintering process can be completed.
Hot isostatic pressing has been widely used in the fields of metal powder sintering, cemented carbide and diamond tool materials. During the sintering process, the hot isostatic pressing technology is implemented by controlling temperature, pressure and time. The pressure applied during the process is multiple times higher than the cold isostatic pressing and the sintering time is greatly shortened. As a result, the molybdenum powders in the pressed and formed parts can achieve higher densification, higher mechanical strength and uniform metallurgical bonds.
Uniaxial pressing applies forces along one direction and can produce molybdenum parts with complex shapes. At the same time, by controlling and using the friction between component, the sintering process temperature and pressure can be reduced and it does not require complex technology supporting equipment. During the process, molybdenum powder is applied along one direction to obtain the necessary pressing force, consequently complete the sintering process.
In conclusion, press-briquetting molybdenum powder sintering mainly includes cold isostatic pressing, hot isostatic pressing and uniaxial pressing. The pressure control during the sintering process, can reduce the sintering process temperature and time, shortening the production cycle and reducing costs. However, specific measurement of the pressure, temperature and time during the sintering process should be implemented based on the characteristics of molybdenum powder materials and application requirements.
