Transient responses of dielectrics during ultrashort pulsed laser irradiation considering non-Fourier heat conduction and nonlocal elasticity

In this study, an electro-thermo-mechanical model incorporating non-Fourier heat conduction and nonlocal elasticity is proposed for dielectrics during ultrashort pulsed laser irradiation. The heat conduction equation and stress constitutive relations are modified based on Guyer-Krumhansl model and nonlocal elasticity. The hybrid representation of the thermoelastic equations is presented. An axisymmetric problem of femtosecond pulse irradiation is considered. The governing equations, adopting hybrid representation, are solved using the finite element method. The transient responses and the influences of thermal relaxation time, thermal nonlocal parameter, and elastic nonlocal parameter are analyzed. The results indicate that thermal inertia effect has a negligible impact on the responses during the laser irradiation of dielectrics. Thermal size effect slows down the temperature drop after laser irradiation and increases the temperature and stresses. Elastic nonlocal effect decreases the stresses, while the wave front is smoothed.