Properties of Machinable Aluminium Nitride
Machinable aluminium nitride is a soft material that comes in two forms: BNP 2 and the more expensive Shapal M. Learn more here.
Machinable aluminium nitride is a technical ceramic that has many applications in high-performance and challenging environments. It has a high heat dissipation capability, as well as excellent mechanical and electrical properties. This is the preferred advanced ceramic material for power-generation industries as well as microelectronics. In both applications there is a vital requirement for rapid and efficient heat dissipation.
Such applications include insulators on high-voltage systems, diffusion furnace process parts and laser components. Aluminium nitride in both its forms – Shapal M and BNP 2 – has a hexagonal crystal structure that is an isomorph of wurzite, a polytype of zinc sulphide. Mineral acids and string alkalis will attack this material along its grain boundaries. The properties of Shapal M and BNP 2 are identical, and the two materials should be machined or otherwise worked in exactly the same way. The difference between them is just cost. BNP 2 is a cheaper version of machinable aluminium nitride.
Over the past decades, aluminium nitride has replaced beryllium oxide – a toxin – in semiconductor industry applications.
This material is stable up to temperatures of 700 degrees Celsius, at which point it begins to oxidise on the surface. Such a layer of surface oxide can be between 5 and 10 nanometres and is capable of protecting the material beneath to temperatures of around 1,370 degrees C. Once temperatures rise beyond this point, the material oxidises in bulk. When it is immersed in a hydrogen or carbon dioxide atmosphere, it is stable up to 980 degrees C.