OPEN ACCESS
The modified alumina has been classified as one of the best thermal insulation materials that able to reduce the solar radiation and enhance the working environment and thus, reduce the energy consumption. This paper emphasis the effect of the multi-variables, such as yeast cell ratio, pressing load, sintering temperatures, and socking time on the lower thermal conductivity of the modified alumina. The ceramic thermal insulation was prepared by semi-dry pressing method using alumina with different amount of the bioactive yeast cell as a pore-forming agent and 3 wt.% sugar. The optimization process was carried out via a genetic algorithm for 61 samples according to the chromosome-based. The microstructure results revealed that there are two types of pores were observed; micro and meso size pores. Furthermore, it was also found by depending on the analyzed input data that the thermal conductivity of 2.5× 10-1 watt/m.oC was acquired at the optimal variables of 1200 oC, 19.4 %, 66 MPa, 1.5 hrs. as sintering temperature, yeast cell, pressing load, and socking time, respectively
thermal insulation, semi-dry pressing, alumina, genetic algorithm
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