http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Evaluation of Hardness and Fracture Toughness in a Porcelain Stoneware with Pseudoboehmite Additions
O. Aguilar-García,S. Bribiesca-Vazquez,J. Zárate-Medina 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.1
The effect of pseudoboehmite additions to conventional stoneware porcelain is investigated. Green compacts were formed by slip casting of stabilized aqueous suspensions and then sintering at 1,150℃, 1,200℃ and 1,250℃. The phase evolution was followed by XRD, the densification degree was calculated from densities and the microstructures were studied by SEM. Hardness, H and fracture toughness, KIC were measured by Vicker’s indentation. When vitrification occurs the presence of the pseudoboehmite leads to a extra mullitization, which has two consequences: a volume expansion resulting in a high porosity and a decrease of the amount of liquid which causes problems with the densification, by these facts the pseudoboehmite particles decrease the fracture toughness of the bodies. The effect of pseudoboehmite additions to conventional stoneware porcelain is investigated. Green compacts were formed by slip casting of stabilized aqueous suspensions and then sintering at 1,150℃, 1,200℃ and 1,250℃. The phase evolution was followed by XRD, the densification degree was calculated from densities and the microstructures were studied by SEM. Hardness, H and fracture toughness, KIC were measured by Vicker’s indentation. When vitrification occurs the presence of the pseudoboehmite leads to a extra mullitization, which has two consequences: a volume expansion resulting in a high porosity and a decrease of the amount of liquid which causes problems with the densification, by these facts the pseudoboehmite particles decrease the fracture toughness of the bodies.
Mixture design to optimize the amount of deflocculants in aqueous porcelain precursor suspensions
O. Aguilar-García,S. Bribiesca-Vazquez,J. Zárate-Medina 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.2
The performance of dispersants poly(acrylic acid), a poly(methacrylic acid), sodium silicate, as well as binary and ternary deflocculant mixtures was compared for highly concentrated aqueous porcelain suspensions. These were formulated in ten stoneware recipes which were processed in the laboratory under fixed conditions, similar to those used in the ceramics industry, and viscosity measurements were made. The use of this methodology enabled the calculation of valid regression models (equations) relating viscosity with the contents of different deflocculant mixtures. The performance of dispersants poly(acrylic acid), a poly(methacrylic acid), sodium silicate, as well as binary and ternary deflocculant mixtures was compared for highly concentrated aqueous porcelain suspensions. These were formulated in ten stoneware recipes which were processed in the laboratory under fixed conditions, similar to those used in the ceramics industry, and viscosity measurements were made. The use of this methodology enabled the calculation of valid regression models (equations) relating viscosity with the contents of different deflocculant mixtures.