Effects of colloidal silica suspension mixing on porosity of phosphate-bonded investments after setting and heating processes

A numerical simulation model, which was based on the setting and heating reactions of the binder phase of phosphate-bonded investment compacts, was developed to compute the porosities of set and burnout compacts. Densities and concentrations of microsilica particles in dilute suspension were measured and input into the simulation model. Validity of the model was confirmed by experimental results, that is, colloidal silica suspensions were prepared using different silica concentrations and mixed with investment powders. Porosities of these set and burnout compacts were experimentally measured. Effects of these factors on the porosity of compacts were examined using the developed simulation model: liquid/powder (L/P) ratio, concentration of microsilica particles in colloidal silica suspension, and ratio of binder component (NH4H2PO4) in investment powder. It was concluded that numerical simulation is a viable tool for dental materials research.

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内容要旨 : LID201506051002.pdf
審査要旨 : LID201506051003.pdf
論文本文 : LID201506051004.pdf
本論文は, 著者Ji-Young BAEの学位論文として提出され, 学位審査・授与の対象となっている。