Process repeatability in abrasive jet micro-machining

A level set methodology for predicting the surface evolution of inclined masked micro-channels resulting from abrasive jet micro-machining at oblique incidence

“…3), and V and f are obtained using (5) and (6), respectively. In (24) and (25), H is non-convex [14], i.e. H is not smooth for all times and positions [15,16].…”

“…For the initial iteration, m¼0, where m¼0,1,2,y is the iteration number, compute H using either (24) or (25), and H Fg using either (30) or (31), for each grid point (i,k) inside the narrow band without the use of extension. For m40, compute the extended Hamiltonian H ext using (24) or (25) …”

“…The fluctuations were most likely caused by the decrease in powder level in the reservoir due to the long machining times required in the experiments [14,24]. The nozzle focus coefficient, b, in the mass flux distribution of (6), and the peak velocity, V 0 , in the velocity distribution of (5), must be measured experimentally.…”

“…This difference in shape arises due to the different erosion laws that govern the surface evolution of the two target materials, i.e. (3) and (4), or in more expanded form, (24) and (25). For PMMA, the local speed of surface erosion is highest when the particle incident velocity vectors are at a shallow angle to the surface, i.e.…”

Abrasive jet micro-machining of planar areas and transitional slopes in glass using target oscillation

“…Care was exercised to enhance the repeatability of the experiments by implementing the suggestions listed in Ghobeity et al (2007c); i.e. using a powder mixer, minimizing the moisture content in the air-powder mixture by using an air dryer and desiccant filter, and keeping the powder bed level approximately constant during operation.…”