Mixing the powder

We leave this preparatory step of the work to our powder suppliers. They supply us in accordance with our instructions and our customers’ wishes with ready-to-use homogenous mixes, plus standard raw materials with factory certification to DIN EN 10204-3.1B. In our laboratory we then carry out control analyses, thus ensuring consistently high quality.

Compression moulding

We compress the metal powder in moulds specifically designed and built for the purpose. The pressure required is based on the surface of the part to be moulded, as well as on the desired density and the required strength and hardness, and is adjusted to suit the sintered part’s intended area of use.

Sintering

The sintering process gives the part the appropriate strength and hardness. This is a fully automatic process that is governed by temperature (up to 1,350°C) and time.

This process is run at below the melting temperature of the alloy’s main component. In order to avoid any oxide formation, an inert gas atmosphere is created within the sintering furnace and is permanently monitored.

As a result of diffusion and recrystalisation processes of the material structure the parts expand or contract.

Fundamentals of calibration

• Redensification
  of the entire part, or partially, to increase
  - density
  - strength
• Postforming
  - bevelling (radii, chamfers)
  - smoothing the surface
• Size accuracy

Finishing

Varies depending on the complexity of the moulded parts

• Machining turning, milling, grinding, slide grinding, honing etc.
• thermally: hardening, tempering, steam treatment, etc.
• Other: plastic impregnation, etc.

Impregnation

Sintered parts, especially sintered sliding bearings, can be impregnated with lubricants. This is done in a vacuum on a time-controlled basis.

Which lubricants are used (generally mineral and synthetic oils or also food-safe oils) is something we agree with our clients based in each case on the intended area of use.

Finished parts

• Packed into client-specified containers
• Dispatched around the globe