Fused silica Introduction  Fused silica is made of high purity crystal silica by electrically fusing (fusing temperature 1800-2000â??) to amorphous Silicon dioxide , then it was classed to different grades by manual and then specially engineered to granular and powder form. Because fused silica has a very low thermal conductivity and excellent thermal shock resistance, it is used in lots of fields of investment casting,refractory,ceramic,epoxy modling compound,fusion bounded epoxy. Fused Silica Properties   Investment Casting Grade 2.1 SiO2 >99.90% 2.2 Al2O3
