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An analytical solution is developed for thermal stress in exponentially time decaying laser short-pulse heating of a metallic surface. Because the heating duration is short, a nonequilibrium heating model incorporating the electron kinetic theory approach is used to formulate the temperature distribution during the laser heating pulse. Thermomechanical coupling is introduced in the analysis to formulate the thermal stress field. Thermodynamic irreversibility is considered and the entropy generation rate due to heat transfer and thermal stress field is formulated during the heating process. It is found that temperature decays gradually in the surface region and becomes sharp as the distance increases towards the solid bulk. Thermal stress is compressive in the irradiated region. Thermodynamic irreversibility due to heat transfer dominates thermodynamic irreversibility because of the thermal stress field. PACS No.: 44.10.+i. Nous presentons une solution analytique pour la contrainte thermique due a une impulsion laser a decroissance exponentielle sur une surface metallique. Parce que le chauffage est de courte duree, nous utilisons un modele de chauffage hors d'equilibre incorporant la theorie cinetique des electrons afin de formuler la distribution de temperature pendant l'impulsion laser. L'introduction d'un couplage thermomecanique permet de decrire le champ de contrainte thermique. Nous tenons compte de l'irreversibilite thermodynamique et nous formulons le taux de generation d'entropie du au transfert de chaleur et au champ de contrainte thermique pendant le processus, pour trouver que la diminution de temperature qui est graduelle dans la region du chauffage devient rapide a distance. La contrainte thermique est compressive dans la region du chauffage. L'irreversibilite thermodynamique due au transfert de chaleur est plus importante que celle due a la contrainte thermique. [Traduit par la Redaction], Introduction Laser short pulse heating of metallic surfaces involves nonequilibrium energy transport in the irradiated region. Electron and lattice subsystems separate thermally because of electron temperature increases through energy absorption [...]

Phonon transport in paired aluminum and silicon thin films is considered under laser short-pulse irradiation at the aluminum film surface. The Boltzmann equation is incorporated to formulate energy transport in the films. To include a volumetric source resembling laser irradiation in the aluminum film, the Boltzmann equation is modified. Thermal boundary resistance is located at the interface of the film pair. An equivalent equilibrium temperature is introduced to assess the thermal resistance of the film during the laser heating process. The phonon temperature obtained from solution of the Boltzmann equation is compared with the findings of the two-temperature model. It is found that phonon temperature obtained from the solution of the Boltzmann equation is lower than that corresponding to the two-temperature model, which is particularly true in the surface region of the aluminum film. Phonon temperature increases gradually while, early on, the electron temperature rises and decays sharply in the surface region of the aluminum film. PACS Nos.: 44.90.+c, 63.20.-e. Nous etudions le transport de phonons dans un film mince d'aluminium et silicium, qui est generee par l'irradiation d'une courte impulsion laser sur la surface d'aluminium. Nous incorporons l'equation de Boltzmann dans la formulation de transport d'energie dans le film et nous la modifions, afin d'inclure les sources volumetriques ressemblant a l'irradiation laser dans le film. La resistance limite thermique est situee a l'interface des deux films. Nous introduisons une temperature d'equilibre equivalente pour verifier la resistance thermique du film pendant le processus de chauffage par le laser. Nous comparons les temperatures de phonon obtenues de la solution de l'equation de Boltzmann avec celles obtenues du modele a deux temperatures et trouvons que les premieres sont plus basses que les deuxiemes, ce qui est particulierement vrai dans la region du film d'aluminium. La temperature des phonons augmente graduellement, alors que celle des electrons monte et decroit brusquement autour de la surface d'aluminium au debut du processus. [Traduit par la Redaction], Introduction Laser short-pulse heating of metallic thin films results in non-equilibrium energy transport in the film. This, in turn, causes thermal separation of electron and lattice subsystems in the thin [...]