Abstract
Sandblast techniques that gas-solid jet impinges on surface of the work are known to process a work surface. Many cases gas is air in general and solid particles are metal, plastics and ceramics etc. The solid particles are accelerated by gas flow and impacts on the work and process it's surface. However the solid particles stream out with gas flow without an impact for fine particles because of large viscosity. For fine processing by means of fine solid particles the viscosity resistance becomes serious obstacle to process surface of the work. When ultrasonic is radiated on the solid particles ultrasonic radiation pressure acts on the solid particles and accelerates it. The radiation pressure is determined by a medium, an acoustic intensity and frequency of the ultrasonic.