Constrained sintering and electrical properties of BNT–BKT lead-free piezoceramic thick films. Issue 2 (1st February 2016)

• Record Type: Journal Article
• Authors: Fan, Pengyuan; Zhang, Yangyang; Huang, Jinqiang; Hu, Wei; Huang, Da; Liu, Zepeng; Xie, Bing; Li, Xiangdong; Xiao, Jianzhong; Zhang, Haibo
• Is Part Of: Ceramics international. Volume 42:Issue 2:Part A(2016)
• Page Start: 2534
• Page End: 2541
• Publication Date: 2016-02-01
• Subjects: Bismuth sodium titanate -- Lead-free piezoelectrics -- Thick films -- Residual stress -- Constrained sintering; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.10.055
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Bi0.5 (Na0.82 K0.18 )0.5 TiO3 (BNKT) thick films were prepared by screen-printing on the alumina substrate. Grain growth behavior, constrained sintering processing, dielectric properties, ferroelectric properties and piezoelectric properties were studied. The results show that BNKT thick films exhibit a much lower grain growth rate and smaller grain size than bulk samples due to the constrained sintering on rigid substrates. The XRD measurement revealed that the residual tensile stress formed during sintering resulting from the constrained in-plane shrinking. The typical 80 μm thick films demonstrate the relative dielectric constant of 775, dielectric loss of 3.6% at 1 kHz, remnant polarization of 18.6 μC/cm 2, coercive field of 61 kV/cm, and longitudinal effective piezoelectric coefficient, d 33 of 105 pm/V at room temperature. Compared with BNT-based piezoelectric bulk ceramics, the smaller longitudinal piezoelectric coefficient is related to the clamping effect of the substrate and the limited extrinsic piezoelectric contributions due to the reduced non-180° domain wall motions.