STUDY ON THE INSTABILITY CHARACTERISTICS OF LIGHT-DRIVEN STIFF-FILM/SOFT-SUBSTRATE STRUCTURE

The surface morphology of film-substrate structure has important application value, and light-driven liquid crystal elastomers can be harnessed to accurately and efficiently control it, which, therefore, have received widespread attention. In this paper, the instability characteristic of light-driven film/substrate structure under tilted illumination is investigated. A theoretical model for the surface instability of light-driven film/substrate structure based on the von Karmen's nonlinear plate theory and the principle of minimum potential energy is established. The critical condition of the instability phenomenon of light-driven film/substrate structure is analytically derived, and the effects of illumination intensity and incident angle on buckling amplitude are discussed. The influence of material parameters on buckling behaviors by using the theoretical model is analyzed. The study demonstrates that changing the light intensity and incident angle can affect the buckling shape, and tuning the light intensity can make significant changes in the buckling amplitude. Moreover, adjusting the angle of incidence of light can finely control the buckling amplitude and alter the parameters of photo compliance, photosensitive component concentration and characteristic length ratio can regulate the buckling shape. The results of this research can help promote the engineering application of light-driven film/substrate structures.