Mechanoluminescence and Optically Stimulated Anti-Stokes Luminescence of Composites Based on Epoxy Resin and Strontium Aluminate Phosphors SrAl2O4:Eu2+, Dy3+ and Sr4Al14O25:Eu2+, Dy3+

Abstract

Composite mechanoluminescent materials (composites) based on epoxy resin transparent in the visible range of the spectrum and fine-dispersed powders of mechanoluminescent phosphors SrAl₂O₄:Eu²⁺, Dy³⁺ and Sr₄Al₁₄O₂₅:Eu²⁺, Dy³⁺ are obtained. The mechanoluminescence and photoluminescence spectra of the composites under the combined influence of short-wavelength (λ = 405 nm) and long-wavelength (λ = 1.06 µm) laser radiation are studied. The attenuation of optically stimulated anti-Stokes luminescence of the composite under the influence of a sequence of pulses of long-wavelength laser radiation is investigated. The composite is preliminarily irradiated with short-wavelength laser radiation. The obtained composite is used to visualize heat propagation and thermal deformations in metal plates arising under the action of high-power laser pulses and the distribution of deformations under mechanical impact. For this purpose, a thin layer of the composite is applied to the surface of the materials under study. The composite had good adhesion to the surface of the materials and a high yield of mechanoluminescence, which allows us to visualize the distribution of temperature and surface deformations with a good spatial and temporal resolution.