Residual Stresses in PZT Investigated by Polarized Raman Piezospectroscopy

Micro-probe Raman piezospectroscopy has been applied to analyse the behaviour of bulk samples of Lead Zirconate Titanate doped with Nb, Sr and Y (PZT-NSY) under mechanical load by performing 4-point bending experiments. The samples experienced different degree of silver migration from Ag electrodes. A residual stress gradient was observed in the proximity of electrodes, due mostly to thermal expansion coefficients mismatch, while in areas unaffected by Ag contamination the stress gradient could be only attributed to the externally applied load.