Abstract
The edge with a consistent and precise shape is important for highly stressed mechanical components. This study investigates the generation, measurement, and definition of edges. Abrasive jet machining, a flexible process ideal for difficult-to-reach areas, is applied for edge generation. A conoscopy laser with small, 25 μm spot size is scanned across the edge for measurement. A B-spline curve is applied to fit the edge profile by an optimization method. Silicon carbide media, 50 μm average size, was used to erode a 90° edge on a workpiece of Inconel 718. Effects of blasting time, stand off distance between edge and nozzle, and orientation of a nozzle are studied. It is found that the edge radius is limited to below 0.15 mm using abrasive jet machining. Under long blasting durations, the edge radius does not change, but collateral damage around the edge is significant. Long standoff distances and high angles of blasting are beneficial in reducing the level of collateral damage. Edge radius is commonly used as the only parameter to quantitatively describe the edge profile. This study demonstrates that a B-spline can provide a better fit and geometrical description of the edge profile.