Abstract
Ultra-fine particles (UFP's ), which have different characteristics in material properties from bulk matter and are useful as a functional material, were produced by pulsated YAG laser. In this process, the plume phenomena by irradiation of laser to titanium were observed by high speed video recorder and the growth rate of the plume were measured. And the production rate of UFP's and the effect of atmosphere were investigated.
As the result, summarized conclusions are followed;
1) The growth rate of the plume was about 26.4 m/s in air.
2) The maximum production rate of titanium UFP's in air was about 6.6 g/hour. It was limited by the maximum ability of 80 J/pulse of laser generator used.
3) UFP's of titanium-nitride of about 20 nm in diameter were produced in the 13.3 kPa (100 Torr) nitrogen atmosphere.
