Fracture Behaviors and Ferroelastic Deformation in W/Cr Co‐Doped Bi4Ti3O12 Ceramics. Issue 6 (8th March 2016)

• Record Type: Journal Article
• Authors: Chen, Yu; Miao, Chengyu; Xie, Shaoxiong; Xu, Luopeng; Wang, Qingyuan; Zhu, Jianguo; Guan, Zhongwei
• Editors: Landis, C.
• Is Part Of: Journal of the American Ceramic Society. Volume 99:Issue 6(2016)
• Page Start: 2103
• Page End: 2109
• Publication Date: 2016-03-08
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.14169
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract : In this paper, the influence of Cr2 O3 additive ( y = 0~0.4 wt%) on fracture behaviors, ferroelastic deformation, and mechanical strengths of Bi4 Ti2.95 W0.05 O12.05 (BTW) Aurivillius ceramics was investigated. For these W/Cr co‐doped Bi4 Ti3 O12 ceramics (BTW– y C), SEM analysis on their fractured surfaces demonstrate that the transgranular fracture is the main fracture mechanism, however, the intergranular fracture also exists in the sample at y = 0.3. Impedance analyses based electrical resonance show that their Poisson's ratio and Young's modulus vary with y in a similar trend, while the frequency constant and elastic compliance exhibit a contrary varying trend with y. On the other hand, under the Vickers indentation, the crack propagation in BTW– y C ceramics takes the form of the long‐straight extension, small‐angle deflection, and short‐distance branching at y = 0, 0.2, and 0.4, respectively. In the uniaxial compression tests, the stress–strain behavior of ceramics consist of three stages, i.e., linear elastic deformation, ferroelastic domain switching, and microcrack propagation. The ferroelastic domain switching tends to form the resistance for the microcrack propagation. Furthermore, uniaxial bending tests prove that the fracture strength is dependent on the grain size and fracture toughness, Overall, the sample at y = 0.1 gains a better mechanical strength among BTW– y C ceramics.