604 金属細線爆発法を用いた窒化物の微細粉末の反応合成(高エネルギー加工,ものづくりにおける基礎研究と先端技術の融合)

Abstract

Nitrides, especially titanium nitride (TiN), aluminum nitride (AlN), and titanium aluminum nitride (TiAlN) have been studied for their novel characteristics. TiN with gold color is used as thin film coating for cutting tool materials due to high hardness, AlN has relatively good thermal and electrical conductivity and is used for heat sinks and similar applications. TiAlN has excellent hardness and oxidation resistance and is used for cutting tools. However, there are many difficulties for synthesizing these nitrides such as microparticulation, extended synthesis time, low purity and high production cost in manufacturing process. An electrical wire explosion technique has been studied for synthesizing nano sized ceramics powders by many researchers. This technique has also been applied for synthesizing TiN powders in liquid nitrogen in our previous work, and nano sized and high purity powders could be recovered in moderate conditions. In the present investigation, titanium wire andaluminum wire were used for synthesizing TiN, AlN and TiAlN. By changing the conditions, the reactivity was clearly changed, and TiN and AlN were successfully recovered in moderate conditions. In the experiment of synthesizing TiAlN, it was not recovered but TiN, AlN and TiAl were recovered. The recovered powders were composed of spherical fine particles in the order of nano-meter. The particle size was observed using scanned electron microscopes (SEM) and the recovered powders were characterized through the X-ray diffraction (XRD).