Coefficient of mean linear thermal expansion (20°C/300°C) Softening pointTransformation temperature:Hydrolyticresistanceat 98°CHydrolytic resistance at 121°C Acid resistance classAlkali resistance classApplications3.3±0.1 (10-6K-1) 820±10°C525±15°CISO719-HGB1 ISO720-HGA1 ISO1776-1 ISO695-A2 Superior heat- resisting products and crafts