Master sintering curve study of alumina-based ceramics

• Main Authors: Ching-Fenq, Wu, 吳慶豐
• Other Authors: Mao-Hua Teng
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/64386206085423752520

碩士 === 國立臺灣大學 === 地質學研究所 === 87 === Master sintering curve (MSC) model, which circumvents the complicated particle geometric assumptions, is capable of predicting the density of a sintered compact for a given powder and green-body process, regardless of its sintering temperature or rate. When the sintering time-temperature profiles and activation energy are known, the sintered density can be predicted through arbitrary time-temperature path. Once had done two or three preliminary experiments that were used to generate the MSC, then by which one can use as a reference to predict the future sintering results. In this study, three systems — pure -alumina, -alumina doped with 300 ppm MgO, and -alumina doped with 500 ppm TiO2 were used. A set of constant heating rate experiments for each system were carried out, and the results were successfully merged into three distinct MSC’s, each with its sintering activation energy 490 kJ/mol, 680 kJ/mol, and 595 kJ/mol respectively. To further test these MSC’s, five sintering experiments with peculiar heating profile were designed and run. The results showed reasonably match with their corresponding MSC, and proved that indeed the sintering experiments will follow a single MSC, independent of their thermal history. On the effect of the error of the density measurement to MSC, analysis showed the error will not affect activation energy, but will shift the MSC to a parallel new position. Furthermore, using sigmoid curve fitting technique in MSC construction is simpler and more reasonable than the polynomial one used in previous studies.