Pulsed photothermal modeling of layered materials

Abstract

Exact analytical solutions of the heat-diffusion problem encountered in the pulsed photothermal evaluation of layered materials are presented. The analysis relates to the long-time decay of the front face temperature following the absorption of a surface heat pulse. The configuration of a coating on a substrate is analyzed, and the parameters governing the temperature evolution are identified with a particular emphasis on the thermal contact resistance term. This model provides a new method of measuring the quality of the interface. Previously published data and new experiments with laminated materials and living tissues are analyzed using the proposed analytical solutions.

Picosecond Transient Thermoreflectance: Time-Resolved Studies of Thin Film Thermal Transport

“…This indicates that the interface between two different metallic layers can alter the thermal transport in a direction perpendicular to the film plane. Dur goal is to use TTR to measure the thermal impedance of interfaces by fitting our results to a one-dimensional heat flow model which includes the interfacial boundary condition [9] aTaT + 1…”

“…As a result, the accuracy of determining the film thermal diffusivity will depend on the precis ion to which the substrate thermal properties are known: The thermal impedance of the film-substrate interface can also complicate the determinat ion of the film thermal properties. Although the theoretical treatments of heat flow in a simple multilayer system are correct, they only account for heat flow across ideal boundaries where there is an abrupt change in thermal properties [6][7][8][9]. In reality.…”

Dynamic Thermal Tomography: New Nde Technique to Reconstruct Inner Solids Structure Using Multiple IR Image Processing

“…This could be clearly traced in the works ofD. L. Balageas, P. Cielo, J.-C. Krapez et al devoted to the effusivity measurements [1,2]. In the USSR, V.Vavilov used the term PHENOMENOLOGICAL DESCRIPTION OF TIIE DIT ALGORITHM Two weIl known relationships between thennal NDE parameters create the basis for DTT.…”

Time-Resolved Infrared Radiometric Imaging of Coatings

“…This approach has elements in common with the technique of photothermal radiometry [3,4] although in our work we use a step heating source as opposed to a pulsed source. We implement our technique with detection using an infrared scanner to allow quasi-parallel acquisition of image data.…”