Sintering or Firing
|Ceramic components being loaded into an electric sintering furnace|
Once the ceramic powder has been compacted and green machined (if required) the “powder compact” is usually around 50% of its final theoretical density. Full densification is achieved by sintering at temperatures up to 1800°C.
The sintering or firing process provides the energy to encourage the individual powder particles to bond or “sinter” together to remove the porosity present from the compaction stages.
During the sintering process the “green compact” shrinks by around 40 vol %. However, this shrinkage is predictable and can be accommodated.