BNC composite ceramic is gray color solid material formed by hot press with hexagonal boron nitride, silicon carbon and zirconia. This material is high strength, toughness, high thermal conductivity, low coefficient of expansion, corrosion resistance with chemicals. It can be easily machined into precision shape like crucible, casting nozzle, continuous casting break rings using standard carbide tooling.Features ◆High thermal conductivity ◆High strength ◆Low thermal expansion ◆Good thermal shock resistance ◆non-stick with metal ◆Microwave transparency ◆Easily machinedDensity≧2.8 g/cm3Heat conductivity≦30W/mkcoefficient thermal expansion≦4.5*10-6/K(RT-1000℃)ColorGrayPorosity≦0.5Compressive strength≧200MPaSINYO is one of the leading and professional gray color hot press boron nitride compound ceramic break ring for metallurgy manufacturers in China. Providing you with good after-sales service and quick delivery, we warmly welcome you to high quality and non-toxic boron nitride products at the most competitive price with us.