Pölymetallurgiaa

Pölymetallurgiaa is the Finnish term for powder metallurgy. It is a metal forming manufacturing process where a metal powder is compacted into a desired shape and then sintered. Sintering is a heat treatment process that occurs below the melting point of the metal, where particles bond together to form a solid mass. This process allows for the creation of complex shapes and parts with specific material properties.

The powder metallurgy process typically begins with the production of metal powders. These powders can be made from a variety of metals and alloys. The powders are then mixed with lubricants or binders to improve their flow and compaction characteristics. Next, the mixed powder is loaded into a die and pressed into a "green" compact. The green compact has sufficient strength to be handled but is not yet fully dense.

Following compaction, the green part undergoes sintering in a furnace. During sintering, diffusion processes occur at the particle boundaries, causing them to fuse together. This results in increased strength and density of the part. Additional post-sintering operations, such as sizing, coining, impregnation, or heat treatment, can be performed to achieve desired dimensional accuracy, mechanical properties, or functional characteristics.

Powder metallurgy is advantageous for producing parts with high precision and complex geometries that are difficult or expensive to manufacture using traditional methods like machining. It is also suitable for creating parts from materials that are difficult to melt or machine, such as refractory metals. Common applications include automotive components, tools, aerospace parts, and medical implants.