Comparative Study of Conventional and Microwave Sintering of Large Strain Bi-Based Perovskite Ceramics

Abstract

A comparative study of microwave and conventional sintering of lead-free Bi 1/2 (Na 0.82 K 0.18 ) 1/2 TiO 3 -BaZrO 3 -CuO ceramics is presented. It was found that microwave sintering (MWS) can be successfully applied to the fabrication of large strain Bi-perovskite with electric field-induced strains comparable to those obtained with conventional sintering (CFS). Although MWS resulted in smaller grained microstructures than CFS, the ferroelectric properties were stronger in MWS-derived specimens than in the CFS-derived ones. The piezoelectric strain constant d 33 * of the CFS-derived specimens reached a maximum value of 372 pm/V after sintering at 1100°C, whereas that of MWS-derived specimens peaked at 950°C with a d 33 * value of 324 pm/V.

Structure and Electrical Properties of Microwave Sintered BTS-BCT-xBF Lead-Free Piezoelectric Ceramics

“…It is found that the grain size tends to be smaller with the increase of BF content, that is, it decreases from 56.72 μm to 18.50 μm as a function of BF, suggesting that the excess BF can inhibit the grain growth. Compared with CS samples, the grain size is smaller in MWS ceramics (see Figure 4 i), proving that the MWS method can also hinder the growth of grain in ceramics; such a phenomenon has been obtained elsewhere [ 22 , 23 , 24 ]. Significantly, the grain size of MWS BTS-BCT- x BF ceramics is close to CS with the increase of doping concentration starting from 0.008, while still a little smaller than the grain size of CS.…”