cip forming，gps sentering，precision machining，stable quality. 

size and precision are according to customization.

silicon nitride ceramic retain some performance as follows：

1. high corrosion resistance, this means they can be also used in strong acid、strong alkali except hf .

2. high temperature resistance. si3n4 ceramic balls can still retain the strength and hardness even the temperature comes to 1000 ℃.in reducing atmosphere it can be used up to 1500 ℃.

3. electrical insulation、non-magnetic.

4. low density(3.26 g/cm3), high rigidity,high strength,high hardness.

5. low coefficient of thermal expansion(3.2×10-6/k), it is nearly 1/4 of the chrome steel, which leads to a good thermal shock resistance of si3n4 ceramic.