title: Mechanical and electromechanical properties of PMNT single crystals for naval sonar transducers.
abstract: PMNT single crystals in the relaxor-ferroelectric lead magnesium niobate (PMN)-lead titanate (PT) system provide significant advantage for underwater sonar transducers. Compared to lead zirconate titanate (PZT) ceramics, the large electromechanical coupling factor provides significant increases in transducer bandwidth. The superior strain energy density generates higher source level across the band, and the lower Young's modulus allows considerably smaller transducers. These payoffs occur even when PMNT crystals are subject to navy operating conditions such as uniaxial mechanical compressive stresses up to 42 MPa, electric fields up to 1.2 MV/m, and a temperature range from 5 to 50 degrees C. The impact of navy-relevant electric fields and mechanical stresses on crack propagation and failure of piezoelectric single crystals is investigated. The compressive, flexural, and tensile strength of PMNT crystals is reported and discussed with respect to conventional PZT ceramics and the operating conditions of a typical naval transducer.
authors.affiliation: Naval Undersea Warfare Center Division-Newport, Newport, RI 02841, USA.
authors.forename: Lynn M
authors.initials: LM
authors.lastname: Ewart
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: McLaughlin
authors.forename: Harold C
authors.initials: HC
authors.lastname: Robinson
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Stace
authors.forename: Ahmed
authors.initials: A
authors.lastname: Amin
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D003460:Crystallization / Q000379:methods*; D004548:Elasticity; D004553:Electric Conductivity; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007854:Lead / Q000737:chemistry*; D008422:Materials Testing; D011825:Radar / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry*; D014159:Transducers
chemical_list: C481719:lead titanate; D007854:Lead; D014025:Titanium