Enhancing densification and electrical properties of KNN-based lead-free ceramics via two-step sintering

Low-Temperature Sintering of Bi(Ni0.5Ti0.5)O3-BiFeO3-Pb(Zr0.5Ti0.5)O3 Ceramics and Their Performance

“…The 1030 • C sintered 0.21BNT-0.05BF-0.74PZT ceramics present explicit resonant and antiresonant shape behavior poled at 25 kV/cm, whereas the maximum phase degree θ is just 34 • , showing the possibility of increasing the poling electric field but constrained by the leakage current of the samples. Such a low θ value accompanied from the beginning by a rather low minus θ degree, i.e., nearly −90 • , is usually observed in the (K 1−x Na x )NbO 3based lead-free piezoelectric ceramics, and the reason is difficult to explain [35]. Based on the resonant spectra, the mechanical quality factor Q m and electromechanical coupling coefficient K p were calculated and are shown in Table 5.…”

(Bi0.5Na0.5)(Zr0.97W0.01Fe0.02)O3 doping effects on KNN‐based lead‐free ceramics prepared via two‐step sintering technique

“…prepared 0.95(Li 0.02 Na 0.50 K 0.48 )(Nb 0.95 Sb 0.05 )O 3 ‐0.05AgTaO 3 ceramics using the two‐step sintering technology. After sintered at the first‐step temperature of 1140°C for 0.5 h and quickly cooled to the second‐step temperature of 1050°C with keeping for 8 h, the electrical properties are significantly improved, among which the piezoelectric constant d 33 is increased to 224 pC/N 35 …”

“…After sintered at the first-step temperature of 1140 • C for 0.5 h and quickly cooled to the second-step temperature of 1050 • C with keeping for 8 h, the electrical properties are significantly improved, among which the piezoelectric constant d 33 is increased to 224 pC/N. 35 In this work, the (1-x)(Li 0.02 Na 0.5 K 0.48 )(Nb 0.95 Sb 0.05 )O 3x(Bi 0.5 Na 0.5 )(Zr 0.97 W 0.01 Fe 0.02 )O 3 (LNKNbS-xBiNZWF, x = 0.035, 0.04, 0.045, 0.05, and 0.055) lead-free piezoceramics were prepared by two-step sintering method, where the perovskite structure stability was improved by adding Li + and Bi 3+ to the A-site of ABO 3 structure and adding Sb 5+ to the B-site of ABO 3 structure. 18,19 The O-T phase boundary was constructed with ions doping combined with adding the (Bi 0.5 Na 0.5 )(Zr 0.97 W 0.01 Fe 0.02 )O 3 (BiNZWF) end component and the T O-T temperature was moved to lower temperature.…”