Technical data: Physical PropertyNo.Physical performanceNumerical ValueUnit1Coefficient of mean linear thermal expansion(20°C,300°C)3.3±0.110-6K-12Transformation temperature525±15°C3Softening point820±10°C4Working point1260±20°C5Density at 20°C2.23±0.02g/cm36Mean thermal conductivity(20°C-100°C)1.2w/m2k7Refractive index0.921
Main CompositionSiO2B2O3Na2O+K2OAl2O3811342
Chemical PropertyHydrolytic resistance at 98°CISO719-HGB 1Hydrolytic resistance at 121°CISO720-HGA 1Acid resistance ClassISO1776-First Class