Analysis of boundary conditions and transient signal treatment in diffusivity measurements by laser pulse method

Lech Pawlowski (1) , Pierre Fauchais (1) , C. Martin

1 LMCTS - Laboratoire de Matériaux Céramiques et Traitements de Surface

A laser pulse method for diffusivity determination is analysed. The method which permits the measurement of the laser pulse energy distribution as well as its shape is developed. This method can be easily implanted into laser pulse diffusivity set-up and it allows to check periodically the pulse characteristics that is of primary importance for the accuracy of the diffusivity measurements. The corrections to the classical model of Parker et al. [1] due to the heat losses and finite pulse duration are then discussed The improvement of the accuracy of the diffusivity measurement through the use of a digitalized data acquisition system (DDAS) is proposed. The smoothing technique of the expérimental, transient thermal signal is developed on the basis of a digitalized Fourier transform. Finally the diffusivity set-up is presented and some results for the standard materials are shown.

Mots clés: diffusion in solids; measurement by laser beam; thermal diffusion; boundary conditions; transient signal treatment; diffusivity measurements; laser pulse method; laser pulse energy distribution; heat losses; finite pulse duration; digitalized data acquisition system; transient thermal signal

Domaines: Articles anciens; Matériaux

Lech Pawlowski, Pierre Fauchais, C. Martin. Analysis of boundary conditions and transient signal treatment in diffusivity measurements by laser pulse method. Revue de Physique Appliquée, 1985, 20 (1), pp.1-11. ⟨10.1051/rphysap:019850020010100⟩. ⟨jpa-00245298⟩