Preparation of textured zinc oxide ceramics by extrusion and spark plasma sintering

Abstract

Since texture was confirmed to improve the properties of ZnO ceramics in various applications, an extrusion–spark plasma sintering (SPS) process was utilised to obtain a textured bulk ZnO ceramics. Rod-like, anisotropic ZnO particles were utilised as the original powder. The particles were aligned in such a position where c axes of the particles were parallel to the extrusion direction after the extrusion process. By spark plasma sintering method, a textured, near full dense homogeneous bulk ZnO ceramics with fine grains was obtained, sintering at relatively low temperature and within short time. Since the orientation was only controlled in one particular direction, i.e. c axis direction, it was a fibre texture that was achieved in this bulk ZnO. The extrusion–SPS process was confirmed to be an effective technique to induce texture in bulk ZnO ceramics.