Measurement of axial and radial thermal diffusivities of materials obtained by uni-axial compaction and sintering of powder
Foued Mzali and Tarek Ben Ameur
Thermophysical properties of cylindrical compacts obtained by uni-axial compaction and sintering of Aluminum alloy 2017 A powder are measured by a photo-thermal method, in which the central region of the cylindrical sample front face is excited with a Xenon-flash source and the temperature rise is recorded on an optimal position (rm) on the rear face. The axial thermal diffusivity (αz), the axial Biot number (Biz) and the radial to axial thermal conductivities ratio (Krz) are then identified, by minimizing the sum of squares of the differences between experimental measurements and numerical results of a 2D model describing the heat transfer in the cylindrical sample. This model is resolved by the finite volume method. Then, the Levenberg-Marquardt method is used for the least squares minimization.
Keywords: Powder compaction, sintering, Flash method, effective thermal diffusivity, porosity.