Analysis of Tungsten Carbide External Impurities

In the process of tungsten carbide manufacturing, it is significant that to control the number and size of internal holes. Too large or too much pores will remarkably accelerate the fracture and speed of tungsten carbide products, which also decrease the strength and toughness of overall alloys. So to study and analyze tungsten carbide impurities plays an important role in improving tungsten carbide process. Analyze through experiments and based on the actual production process, there are many causes of tungsten carbide external impurities, such as impurities in the air, metal impurities, oxide particles impurities and so on.

Since long tungsten carbide manufacturing process, the introduction of external impurities channels is multi-faceted, such as dust in the air, human hair, etc, which is likely to introduce impurities from mixing, sintering, stored in the transport and other processes. These impurities are largest in number after sintering is also often difficult to remove effectively in a subsequent step. In order to solve this problem requires the operator to strictly abide by the rules, to minimize the human factor introduced by the impurities; secondly, as far as possible it should be fully enclosed production lines and hot isostatic pressing (HIP) method to reduce the dust in production workshop.

The introduction of metal impurities is mainly caused by the equipment used in the production of cemented carbide, such as mesh sieve granulation rub broken when it been used; ball milling cylinder wall is rubbed crumbs mixed with metal powder; some debris and equipment due to corrosion, aging and other factors may cause the introduction of cemented carbide impurities. Most of the metal impurities are lower than the melting point of carbide materials and carbide and impurities has different degree of shrinkage, so In the sintering process will first melt and penetrate into the edge of the cemented carbide powder particles, and the binder phase Co compromised; adhesion and wettability deteriorated; edge adverse tissue contraction, resulting the hole. Thus we should pay attention to the screen usage, comply with operating procedures and regularly inspect the equipment corrosion, aging phenomenon.

• < Prev
• Next >