An inverse method for the abrasive jet micro-machining of high aspect ratio channels of desired topography – Part II, experiments

Abstract

Part I of this two-part paper presented an inverse technique to sculpt high aspect ratio (AR) micro-channel cross-sections of desired topography. In this paper, the methodology is experimentally verified for a variety of topographies machined in both brittle and ductile erosive materials. Micro-channels with trapezoidal and semi-circular cross-sections, and semi-circular protrusions were machined in borosilicate glass. Micro-channels with symmetric and asymmetric wedge-shaped cross sections were machined in poly-methyl-methacrylate PMMA. The chosen topographies represent the most challenging cases because they run counter to the natural surface evolution tendency for these two materials. Overall, the average error between the machined and desired profiles was 6.4% in borosilicate glass and 9% in PMMA. The methodology opens up new possibilities for the micro-fabrication of higher efficiency devices containing high-aspect ratio micro-features of virtually any desired shape.