Compaction is an important production process in the production of powder metallurgy parts.

The pressing process of powder metallurgy is divided into four steps. First, the preparation of powder involves the preparation of materials. According to the material requirements, the ingredients are prepared according to the formula, and then the mixture is mixed. This method mainly considers the particle size, fluidity and bulk density of the powder. The particle size of the powder determines the gap between the filling particles. Use the mixed materials immediately, and do not leave them for too long. Long time will lead to moisture and oxidation.

The second is to press the powder. There are mainly two pressing methods commonly used in the process of powder metallurgy, namely one-way pressing and two-way pressing. Due to different pressing methods, the internal density distribution of products is also different. In simple terms, for unidirectional pressing, with the increase of the distance from the punch, the friction force on the inner wall of the die reduces the pressure, and the density changes with the change of the pressure.

Lubricants are then usually added to the powder to facilitate pressing and demoulding. During the pressing process, the lubricant reduces the friction between the powders at the low pressure stage and rapidly increases the density; However, in the high-pressure stage, as the lubricant fills the gap between the powder particles, on the contrary, it will hinder the density of the product. Controlling the release force of the product avoids the surface defects caused by the demoulding process.

In the powder metallurgy pressing process, it is necessary to confirm the product weight, which is very critical, because the unstable pressure in many factories will lead to excessive weight difference, which directly affects the product performance. The pressed product must be blown off the residual powder and impurities on the product surface, placed neatly in the appliance and prevented from impurities.