New Sintering Furnace

Posted on by

International Syalons (Newcastle) Limited have recently installed and commissioned a new, large, state of the art sintering furnace, which significantly extends our sintering capacity.

The furnace, built by Vacuum Furnace Engineering Ltd (VFE) of Halesowen, West Midlands, UK, allows us to manufacture sialon parts up to 2m in length, significantly longer than our previous maximum length of 1.5m. Thermocouple protection sheaths for molten metal handling, are now available in this new length at a diameter of 28mm.

In addition, the extra capacity, 6 times our previous capacity, will allow us to manufacture parts up to 600mm in diameter, far larger than the previous maximum diameter of 200mm.

For more information on our on the products we manufacture, please contact us.

Silicon Nitride Ceramics

Posted on by

Silicon nitrides (Si3N4) are a range of advanced engineering ceramics characterised by high strength, toughness and hardness and excellent chemical and thermal stability.

Silicon nitride was discovered in the mid-nineteenth century but did not lend itself to ease of fabrication, due to its covalently bonded nature. This initially led to the development of two types of silicon nitride, reaction–bonded silicon nitride (RBSN) and hot pressed silicon nitride (HPSN). Subsequently, since the 1970s two further types have been developed: sintered silicon nitride (SSN), which include the sialons, and sintered reaction–bonded silicon nitride (SRBSN).

Continue reading→

R & D Engineer/Science Graduate Position

Posted on by

International Syalons (Newcastle) Limited are the UK's leading manufacturer of advanced nitride ceramics. We are a small but fast–growing, well–established manufacturing company supplying advanced ceramics to industries such as oil and gas, automotive and molten metal handling.

Continue reading→

Designing with Ceramics

Posted on by

This guide is aimed at engineers and designers wishing to incorporate advanced technical ceramics, such as silicon nitride and sialons, alumina, zirconiaor silicon carbide into their design.

Often an engineer unfamiliar with using ceramics will want a direct copy of a component that was originally metal, for example, made in ceramic. Very often this is not the best solution and can unnecessarily increase manufacturing costs and even result in the component not working as desired.

Continue reading→

Development of Syalons

Posted on by

Silicon nitride (Si3N4) was discovered in the mid-nineteenth century and caused no excitement among the engineering fraternity of the day. The problem was that Si3N4 does not lend itself to ease of fabrication.

Over the next century two principle routes for fabricating Si3N4 ceramics were developed: hot pressing and reaction bonding.

Hot pressed Si3N4 (HPSN), was made by adding a flux (usually magnesia, MgO) to a fine Si3N4 powder and then pressing the powder in a graphite die at high pressure and temperature. The resultant HPSN body, although fully dense and extremely strong, could only be made in to simple shapes which would then require expensive diamond grinding to obtain the desired profile.

Continue reading→

What are Sialon Ceramics?

Posted on by

SiAlONs are ceramic alloys based on the elements silicon (Si), aluminium (Al), oxygen (O) and nitrogen (N) and were developed in the 1970s to solve the problem of silicon nitride (Si3N4) being difficult to fabricate.

As alloys of Si3N4, SiAlONs exist in three basic forms. Each form is isostructural with one of the two common forms of Si3N4, beta (β) and alpha (α) and with silicon oxynitride. The relationship between that of SiAlON and Si3N4 is similar to that between brass and pure copper. In the latter case, copper atoms are replaced by zinc to give a better and stronger alloy than the mother metal. In the case of SiAlON, there is substitution for Si by Al with corresponding atomic replacement of N by O, to satisfy valancy requirements. The resulting 'solution' (SiAlON) has superior properties to the original pure solvent (silicon nitride).

Continue reading→