Abstract
A novel in-situ Raman spectroscopic observation system was established to investigate the microscopic behaviors of lanthanum-doped lead zirconate titanate (PLZT) polycrystalline ceramic under a coupled mechanical-electrical load. The compressive stress ranging from 0 MPa to 548.8 MPa and the constant electric field of 2000 V/mm were simultaneously applied to the as-prepared rectangular PLZT specimen with a typical tetragonal structure and an empirical composition of Pb0.86La0.10Zr0.57Ti0.43O2.86. It was found that the 5-time averaged in-situ Raman spectra obtained within the same grain in the PLZT ceramic by varying the polarization direction from 0° to 180° were susceptible to the coupled mechanical-electrical load. The Raman intensity (I) and the polarization angle (θ) may be related by I = Im sin (2θ + φ) + k. Under the action of the same intensity of the incident light, the variations in the fitting parameters k, Im, and φ might be referred to the changes in the orientation distributions and material constants of Raman tensors. The polarization direction for the Raman scattering intensity reaching maximum (θmax) may be determined by\( \kern0.5em 2{\boldsymbol{\theta}}_{\mathrm{max}}=\frac{\pi }{2}-\boldsymbol{\varphi} \). The apparent reduction in Raman intensity and slight enhancement in θmax were observed under a coupled mechanical-electrical load.