Conventional PM Process
The most common PM process – often referred to as conventional PM processing – involves compressing metal powder in a precision tool set and then heating it to form metallurgical bonds. The resulting sintered part is very often the end product, secondary operations are not necessary, one of the main benefits of powder metallurgy.
A further significant advantage is that the PM process conserves natural resources by utilizing recycled raw materials. A low emission manufacturing process and avoiding or minimizing wasteful secondary operations, further minimise environmental impact.
The PM process uses highly consistent, engineered elemental or alloyed metal powders. Although the majority of products are manufactured from material compositions defined by national or international standards, GKN also focuses extensively on the development of unique materials for specialized applications.
The raw material powder is subsequently pressed or compacted in a closed die to form the near-net-shape (identical to or very similar to final dimensions) "green" compact. We leverage our internal tooling design and manufacturing capability to optimise this process. Our manufacturing facilities are equipped with the most advanced commercially available equipment as well as our own advanced CNC presses, designed and built in-house.
The "green" compacts are subsequently heated in a continuous sintering furnace to an elevated temperature and in a protective atmosphere in order to form metallurgical integrity. Consistency is assured by applying precise temperature and atmospheric controls. GKN has focused on the standardization of sintering equipment as a key element of best practice.
Secondary operations are selectively applied to either improve dimensional tolerance, or to achieve geometries that cannot be formed in the compaction process. Sizing is a high speed pressing operation process which improves profile tolerance. Typical machining processes such as turning, milling, drilling and threading can be applied when required. PM products can be successfully joined to other PM or non-PM products using various processes.