Study On Microstructure And Properties Of Photocurable 3D Printing Ceramic Cores

This paper mainly studys the influence of silicon dioxide and zirconium dioxide additive in ceramic slurry on microstructure and performance of ceramic cores based on stereolithography.It studys the variation of performance of the ceramic cores with different solid content(40vol%,42vol%,44vol%,46vol%,48vol%and 50vol%)and different additive content(Owt%,0.5wt%,1.0wt%and 1.5wt%).It also studys the transformation law and forming mechanism of the phase composition in ceramic cores.It discusses the influence of the phase composition on the comprehensive performance of ceramic cores.The following main research results are obtained:Without additives,after 3D printing and sintering at 1300?C shrinkage and porosity of ceramic cores decrease with the increase of silica content.However,the flexural strength at room temperature and high temperature obviously increase with the increase of silica content.When the content of zirconia additive is constant,the trend is consistent with that without additives.Both shrinkage and porosity of ceramic cores decrease with the increase of silica content.The flexural strength at room temperature and high temperature increases with the increase of silica content.However,when the silica content is constant,the shrinkage decreases with the increase of content of zirconia.The porosity and flexural strength increase with the increase of content of zirconia.After degreasing and sintering,the larger SiO2 particles in ceramic cores are bonded together by the smaller SiO2 particles.When the silica content is low,it is easy to have microcracks on large particles.And the number of microcracks increases obviously after high-temperature bending test at 1600?.However,the number of microcracks decreases because of the increase of silica content.When the silica content is constant,the number of microcracks decreases with the increase of zirconia content.After degreasing and sintering,the quartz and cristobalite transform into?-cristobalite and amorphous quartz glass.After high-temperature bending test at 1600 ?,?-cristobalite and amorphous quartz glass absolutely transform into a-cristobalite.With the addition of zirconia additive,part of silica reacts with zirconia to form zirconia silicate.