|Injection Moulded Silicon Carbide Components|
In a similar manner to extrusion, a plastic mix is prepared and heated in the barrel of the moulding machine until it is at the correct temperature at which point the mix has a sufficiently low viscosity to allow flow if pressure is applied.
A plunger is pressed against the heated mixture forcing it through an orifice and on into the tool cavity. The moulded part is removed from the die and the organic binder slowly burnt out in a controlled atmosphere by means of a carefully controlled heating schedule, prior to sintering.
Low Pressure Injection Moulding
Technology has jumped forward in great leaps and bounds over the last ten years to arrive at a position were high-volume ceramic components can be made using injection moulding techniques.
Injection moulding of ceramic components has several major benefits over more traditional manufacturing techniques such as die pressing and green machining.
Excluding the obvious; that it is a good technique for very high volume parts, injection moulding has also proved to be an excellent technique for making components such as turbo charger rotors and thrust bearings which would be too expensive if the parts were machined.
Low pressure injection moulding (LPIM) provides an excellent option for producing ceramic components using low cost tools in comparison to high pressure moulding techniques.
The LPIM process enables fabrication of very complex shapes as well as simpler components. The essence of the process is that parts can be produced with a higher level of integrated function to meet the customers needs then other process are able to achieve.
The main process features are: