New Processing of Textured Ceramics by Colloidal Processing Under High Magnetic Field
The controlled development of texture is one of the ways for effective in improving the physical and mechanical properties. We’ll demonstrate new processing of textured ceramics as an example of alumina by slip casting in a high magnetic field and subsequent heating. Susceptibility of diamagnetic α-alumina is very small, but the orientation energy of alumina particle by a high magnetic field becomes larger than the thermal energy. α-alumina of a rhombohedral structure shows anisotropic susceptibility, but this anisotropy has up to now been more or less ignored due to its very low value. However, in a high magnetic field the energy of crystal anisotropy becomes comparable to or larger than the energy of thermal motion. The degree of orientation depends on processing factors such as heating temperature, particle size, magnetic field and concentration of suspension, etc. This process technique confers several advantages and it is possible for this type of processing to be applied to other non-cubic ceramics, such as TiO2, ZnO, SnO, HAP, AlN, SiC, etc.
Wei Pan, Jianghong Gong, Chang-Chun Ge and Jing-Feng Li
Y. Sakka and T. Suzuki, "New Processing of Textured Ceramics by Colloidal Processing Under High Magnetic Field", Key Engineering Materials, Vols. 280-283, pp. 721-728, 2005