Finite Element Determination of Thermal Conductivity of SiAlON Ceramics Using Sem Images

Year 2009, Volume: 1 Issue: 1, 11 - 15, 15.01.2009

İbrahim Uzun , Zühtü Pehlivanlı , Battal Doğan

Abstract

The thermal conductivity for SiAlON ceramics which are used as a cutting tool material in manufacturing industry has been investigated experimentally, theoretically, and finally numerically. In the experiments, the flash technique was used to determine the thermal conductivity by using the measured thermal diffusion coefficient data in the unsteady regime. Using Maxwell’s, serial, and parallel analytical models, the theoretical thermal conductivities have been determined.
For the numerical study, the Scanning Electron Microscope (SEM) images of the material were used. From these images,
a thermal Ansys® model has been generated through which the effective thermal conductivity was determined. Due to
the non-uniformity of the distribution of the boundary phase, different enlargement ratios of the images and as a result
finer meshes affect the calculated thermal conductivity values of the ceramics. The experimental and especially the
numerical analysis results in this study gave thermal conductivity values which agree quite well with each other.

Keywords

Effective thermal conductivity, SiAlON, ceramics, SEM

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