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To (Pb 0.70 the Ba 0.26 Sr (0.04)) (Zr 0.52 Ti (0.48)) O 3 ( based material PBSZT); through of Bi 2 O 3 doped to add potassium titanate the whiskers (KTOw), as well as composite Bi 2 O 3 doping and to add potassium titanate whiskers are three ways to improve the mechanical properties (bending strength (σb), breaking strain (△ ρ)). With the scanning electron microscope (SEM) and x-ray diffraction (XRD) The structures and physical characterization of ceramic samples the phase composition, the component of the x-ray analysis of samples; Characterization of the functional properties of the sample through the associated instrumentation: relative dielectric constant (sr ), dielectric loss (tanδ), hysteresis loop, the piezoelectric strain constant the (d 33 d 31 ), electromechanical coupling coefficient (K p ). Right amount the Bi 2 O 3 (0 to 0.3 wt%) doped allows the Bi-PBSZT ceramic grain refinement, increase the density, σb increases; Bi 3 replace pb 2 the Bi-PBSZT lattice change, the glass phase Pb enrichment at the grain boundaries Bi 3 and A bit pb 2 vacancy dipole moment between the depressing effect of the ceramic εr and d of 3 decline. Bi 2 0 3 doping amount of 0.3 wt.% Bi-PBSZT ceramic performance optimization, σb to 140.37 MPa εr of 5520, d 3 1 518 × 10 -12 m / V. In the ceramic structure, the KTOw added introduction of the uniform distribution of micropores, (10μm), to form micropores toughening mechanism, and improve the breaking strain of the specimen, with the the KTOw content increases, the ceramic density decreases, the intensity decreased; KTOw addition on features, which the ε r , tan δ decreased, while the d 3 3 performance parabola opening down-change, K p and its consistent with the change. Compared PBSZT, the KTO w adding 0.5 wt.% D 3 3 reached a maximum value of 471.4 × 10 -12 m / V, to improve 26.2%, △ ρ improve 4.2%; KTOw addition of 1.0 wt.% d 3 3 dropped 3.9%, the and △ ρ achieve maximum value of 2.45 mm, a 28.9% increase. The role of the emergence of the \Bi 2 O 3 and KTOw simultaneously play their respective efficacy, flexural strength, dielectric properties, piezoelectric properties of the composite is the unimodal modified results, while breaking strain greater increase. Is at 0.3 wt% of Bi 2 O 3 the obtained composition modified with 1.0 wt.% KTOw composite specimen fracture deformation reaches a maximum 3.18, compared PBSZT an increase of 67.3%, σb to 101.51 MPa, d 3 3 to 362.5 × 10 -12 m / V. 0.3 wt% Bi 2 O 3 with 1.8wt% KTOw, 0.5 wt% Bi 2 O 3 with 1.0wt% KTOw 0.5 wt% Bi 2 O 3 and 1.8 wt.% KTOw several combinations appear piezoelectric ceramic fracture deformation The piezoelectric constant Dual liter phenomenon. This while improving the toughness of piezoelectric ceramics and piezoelectric results highlight the advantages of composite way.
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