Investigation of crystallographic and bulk strain in doped lead magnesium niobate

摘要: Using an in situ x-ray diffraction (XRD) technique, the electric-field induced change d-spacings Δd/d of individual microcrystals or “crystallographic” strain is measured on lead magnesium niobate—lead titanate—barium titanate electrostrictive ceramics composition 0.970(0.900PMN−0.100PT)−0.030BT from zero field to saturation. This crystallographic then compared bulk longitudinal as by Δl/l using a photonic sensor. The behavior for virgin samples could be fit constitutive model, where proportional square polarization with coefficient Q determined 1.4 (×106 cm4/C2). Attempts same sample required lower values Q∼1, and generally yielded worse fits model predicted greater than observed at low electric fields. Subsequent XRD measurements pre...