Influence of texture on electrical properties of ZnO ceramics prepared by extrusion and spark plasma sintering

• Published in: Ceramics international Vol. 33; no. 1; pp. 107 - 114
• Main Authors: Ning, Jiang Li, Jiang, Da Ming, Kim, Kyoung Hun, Shim, Kwang Bo
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2007; Elsevier Science
• Subjects: A. Extrusion; Applied sciences; Building materials. Ceramics. Glasses; C. Electrical properties; Ceramic industries; Chemical industry and chemicals; D. ZnO; Electrotechnical and electronic ceramics; Exact sciences and technology; Technical ceramics; Texture; A. Extrusion; D. ZnO; Texture; C. Electrical properties; Scanning electron microscopy; Plasma; Electrical properties; Experimental study; X ray diffraction; Oxide ceramics; Spark discharge; Transmission electron microscopy; Sintering; Extrusion; Zinc oxide; Property structure relationship; Manufacturing; Electroceramics
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2005.08.005

An extrusion-spark plasma sintering (SPS) process was successfully utilized to obtain a textured, near full dense homogeneous bulk ZnO ceramics. Rod-like, anisotropic ZnO particles were extruded and sintered, and highly c-axis-preferred orientation was obtained in the bulk ZnO, which can be called as fiber texture. The textured bulk ZnO showed more low-angle grain boundaries compared with that without texture. It was found that the highly preferred orientation decreased the electrical resistivity obviously in the bulk ZnO at room temperature. The observed high proportion of low-angle grain boundaries due to the texture resulted in a quite lower resistivity in grain boundaries at room temperature, which was the main reason for the reduction in electrical resistivity of the textured bulk ZnO ceramics.