Spark plasma sintering of transparent aluminum oxynitride
Development and modernization of small arms for the army makes it necessary to develop means of body armor. In particular, improved mechanical properties required of transparent armor materials used as armored glass. The most promising material for transparent ceramic armor is based on aluminum oxynitride (ALON).
Ranked among presented in the present time of ceramics, with an average density of aluminum oxynitride has a sufficiently high strength comparable to the YAG (yttrium aluminum garnet) and cubic zirconia (stabilized zirconia). And the most important characteristic for body armor - toughness - ALON surpasses all transparent materials (including quartz glass - fused quartz, spinel and leucosapphire).
Typically made from aluminum oxynitride powder mixtures of aluminum oxide and aluminum nitride. To obtain the required mechanical and physical properties of the resulting material required density, as close as possible to the theoretical. It is also important to obtain a single-phase structure. Any inhomogeneity and second phases prevent light transmission.
To achieve the desired properties is also very important to make the preparation of raw material: powders of Al2O3 and AlN. In preparation for sintering powders may include: grinding in ball mills, and other, stirring, in a liquid dispersion and drying. Also important is the initial state and powder parameters such as particle size, purity, etc.
In this paper, attention is paid to the use of spark-plasma sintering to obtain transparent ceramics based on aluminum oxynitride, as well as the study of powder sintering cooking modes.