Fully dense Silicon Nitride
Fully dense Silicon Nitrides (i.e. 0% porosity), are made in a number of different ways. Each has a defining characteristic that makes it stand out as the number one choice in any given market. This is provided by the combination of the outstanding hardness, excellent wear resistance, excellent chemical corrosion resistance and superior thermal shock capabilities. This is being seen in two of the biggest growing markets, the Semiconductor industry and the Bearing market who are both experiencing uninterrupted runs due to the longer life of this material.
The fully dense process creates parts from both fine grain Si3N4 powder and sintering aids which are formed together via methods such as pressing, iso-pressing, hot pressing and hot isostatic pressing. Depending on the process route a final sintering stage may be required to make the products fully dense. During the sintering process shrinkage occurs (up to 20%) to give the final fired component. Following the firing stage the parts are diamond ground to give the required geometry and finish. The onsite grinding capabilities allow us to machine to very tightly tolerance dimensions and finish parts to sub-micron finish.
The choice of material for the specific application is dependant on cost and properties of components required. RBSN is the lowest cost material of the Silicon Nitride family, there is then a large step up to the characteristics displayed by the fully dense Silicon Nitrides. All exhibit similar mechanical properties dependant on the different grades and processing routes available. These can also be tailored to individual requirements with advise provided from our highly experienced technical team.
Typical Applications of Silicon Nitride:
- Molten metal handling (including crucible / wear plates)
- Wire guides
- Brazing jigs
- Induction heating coil supports
- Reinforcement phase for composites
- Welding jigs, fixtures and weld location pins
- Dental heat treatment supports
- TIG / Plasma welding nozzles
- Thermocouple sheaths
- Bearings and rollers
- Glow plugs
- Cutting tools
