The Prepation Technology Study Of High Density Fused Silica Ceramics

In this paper,in order to solve dense fused silica ceramic is not high gel-casting prepared.Studying on the impact of solid content,monomer concentration,dispersant relevant process parameters based on low toxicity gel system.And made a high solid,low viscosity slurry,combination of physical vibration method such that the green densification.The results showed that: solid content of 63% ?dispersant1.5wt%,p H value of 4,The resulting slurry best performance,standards-compliant high solids,low viscosity.Monomer concentration of 8wt%,the bending strength of the sample up to 16 MPa,combined with ultrasonic vibration method can reduce the green bubbles to obtain a high density of green.This paper with a novel sintering technique-Microwave sintering technology for fused silica ceramics sintering,with SiC heating sheet.The results showed that: low-temperature sintering stage,the output power of 1500 W,pre-heating rate of 5 ? / min,raised to 600 ?degreased,sintered late output power of 2000 W,heating rate of 25 ? /min,increased to 1150 ?,heat 2h,the bending strength can be sintered36.3Mpa,a bulk density of 1.93 g / cm~3 highly dense article.Compared to conventional sintering,the improved performance of the article,while increasing the efficiency of the sintering.Try using carbon thermal reduction method of fused silica ceramic powder pretreated,with traces of nitrides,and the use of pre-treated fused silica powder Gelcasting.The results show that: in a dynamic nitrogen flow rate of 5L / min of access,at 1100 ? successful introduction of the micro-nitride,fused silica powder phase transition does not occur.Add nitride ceramics and fused silica did not influence the sintering temperature,the preconditioned ceramic powder fused silica molded articles bending strength can be sintered 39.6MPa,a bulk density of1.96g/cm~3,can be improved to some extent,dense fused silica ceramic.Paper combine viscosity tests,Zeta potential measurement,XRD,XPS,SEM,FTIR,flexural strength testing.The resulting sample to reach the expected target sample requirements,but put its densification study tothe large size sample of the market research,there are many needs further research and improvement.