1983 Volume 49 Issue 11 Pages 1540-1548
The present research aims to realize the numerically controlled ultra-precision machining which can easily finish the work into an arbitrary shape by a single apparatus, utilizing the elastic fracture of the order of atomic size. Ultra fine powder particles and water are mixed, and making the rotating sphere of polyurethane rubber approach to the material surface, the state of fluid lubrication of the mixed fluid is realized, so that powder particles in the mixed fluid are made to arrive on the surface. Then the elastic fracture of atomic size is achieved. In this report, the fluid motion between the rotating sphere and the work surface, and the movement of powder particles is introduced furthermore, the film thickness of fluid is measured, and the machined surfaces are observed. The following results are obtained. (1) The calculated value of the film thickness with EHD theory is good consistent with the measured value. And it is realized that the peripheral velocity of the polyurethane sphere has a great influence on its value. (2) Fluid film thickness which is caused by elasto-hydrodynamic lubricating state is much larger than the diameter of the powder particle, so this machining is not carried out with damage to the work surface which is the result of compulsive scratch, but is done by the fracture of the order of atomic size with no damage to the finished work surface.
