MECHANICAL AND ELECTROMECHANICAL PROPERTI ES OF MONOCLINIC ZRO2 FIBERPZT COMPOSITES/

Mechanical and electromechanical properties of monoclinic ZrO2 fiber/P ZT composites fabricated by slip casting and ordinary sintering were e xamined. Bending strength of the composites decreased by increasing th e fiber content from 0 to 20 vol%, However, the composite containing 5 vol% ZrO2 fibers yielded a fracture toughness K-IC of 1.4 MPa.m(1/2), 75% higher than that of PZT matrix. The measurement of thermal expans ion and observation of microstructure suggest that microcracking, crac k bowing and crack deflection contribute to the increase in K-IC. Addi tion of ZrO2 fibers reduced both permittivity and coupling factor K-31 Of the composites. At 5 vol% ZrO2, the K-31 value of the composite wa s 25% lower than that of PZT matrix.