Enhancement of mechanoluminescence sensitivity of SrAl2O4: Eu2+, Dy3+/Epoxy composites by ultrasonic curing treatment method

In this paper, we present a novel approach to enhance the mechanoluminescence (ML) sensitivity of composite made with epoxy resin and strontium aluminate co-doped with europium ions and dysprosium ions (SrAl2O4: Eu2+, Dy3+) (SAOED) by subjecting it to ultrasonic vibration throughout the curing process. Three different SAOED particle size models were subjected to different ultrasonic frequencies; 200 kHz; 120 kHz; 40 kHz and control 0 kHz, in order to investigate the effect of sonication frequency on ML sensitivity. A series of fractography analyses was conducted using scanning electron microscopy (SEM) images to reveal the changes in interfacial bonding integrity. Also, micro-computed tomography (micro-CT) test was conducted to examine the particle dispersion and morphology in the composites. Physical mechanisms on how the ultrasonic curing treatment (UCT) can enhance the interfacial bonding strength was discussed.