Lead lanthanum zirconate titanate (PLZT)-based fiber composites for enhanced photostrictive actuation: a numerical study

Only a few piezoelectric materials interact with light owing to their wide bandgap, which leaves researchers with very few options. The high piezoelectric coupling coefficient of lead lanthanum zirconate titanate, i.e., PLZT (Pb_0.92La_0.08(Zr_0.65Ti_0.35)_0.98O₃), makes it very popular amongst the research fraternities. In this paper, piezoelectric coupling coefficient is further improved by designing a 1–3 composite of PLZT as matrix and fibers of PMN35PT (Pb(Mg_1/3Nb_2/3)O₃–0.35PbTiO₃). First, a finite element method is applied to representative volume elements of 1–3 photostrictive composites to determine the elastic, piezoelectric, pyroelectric, and thermal expansion coefficient. Secondly, degenerated shell element-based finite element formulation is used to simulate the actuation response of host structure bonded with 1–3 photostrictive composite, while prescribed with cantilever and simply supported boundary conditions. It is observed that the 1–3 composite of PLZT and PMN-35PT has 15% higher piezoelectric coupling coefficient and its pyroelectric coefficient is 7.5 times of PLZT material. Keeping the constant geometrical and boundary conditions, the structure equipped with the proposed 1–3 photostrictive composite produces a 74.8% enhanced actuation response.