The purpose of this paper was to prepare ultrafine particles of Si-based intermetallic compounds, TiSi2, MoSi2 and VSi2, by an arc plasma method with hydrogen addition. The properties of the prepared particles were affected by the vapor pressure ratio (Ti/Si, V/Si: 10-1; Mo/Si: 10-3) of the constituent metals. The vaporization and condensation rates of the constituent metals should be controlled to prepare intermetallic compound particles in the case of large different vapor pressures. The vaporization rate can be controlled by H2 concentration in the arc; for example, an increase in H2 concentration leads to an increase in Ti fraction in the prepared particles in a Si-Ti system. The preparation of ultrafine particles of TiSi2 was most successful from the 60-wt.% Ti raw material with the 50%-H2 arc. MoSi2 particles were prepared from the 85-wt.% Mo raw material with the 50%-H2 arc. A single phase of VSi2 particles was prepared successfully from the 60-wt.% V raw material with the 50%-H2 arc. Another purpose was to investigate the mechanism of vaporization enhancement of particular metals from a metal mixture by hydrogen in arc plasmas. The vaporization enhancement was mainly attributed to the formation of intermediate products such as hydride and/or activity modification by hydrogen in molten metals.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry