Effect of uniform laser irradiation on thermal response of temperature sensitive structures

The analysis of the temperature distribution, thermal deformation, and stress of thin plate structures attributed to laser irradiation is of great significance because the thermal effects substantially affect a suite of properties. In this paper, based on the theory of thin plate thermal bending, the analytical expressions of deflection and thermal stress in the local uniform temperature field are derived and compared with the numerical simulation results. The influence of the boundary constraint and irradiation factor on the thermal response is analyzed. Considering the temperature sensitivity of material parameters, the effect of heat flux density on the structural response is analyzed by the finite element method. The results show that the analytical solutions of the circular plate deflections are consistent with the numerical results. The maximum values of both deflection and compressive stresses occur at the center. The maximum tensile stress occurs near the boundary of the spot. In the heat affected zone (HAZ), the deflection of a point shows a trend of the Gaussian decrease with the increase in the distance to the center, while the thermal stress almost does not change with the distance. Outside the HAZ, both deflection and thermal stress are related to the boundary conditions and irradiation factors. Considering that the material parameters change with temperature, the HAZ area, deflection, and von Mises stress are positively correlated with the heat flux density, but the change patterns are different.