Impact of Nozzle Design on Surface Roughness of Abrasive Jet Machined Glass Fibre Reinforced Polymer Composites

Abrasive jet machining is widely used for machining composites. Glass fibre composites find extensive use in aerospace industries, automobile sectors, medical fields and marine applications. Their usage in automated engineering industry needs a good surface finish. Glass fibre reinforced polymer composites are difficult to machine with conventional machining techniques. Hence, in this paper, abrasive jet machining of glass fibre reinforced polymer laminates was experimentally investigated for the various parameters in terms of average surface roughness (Ra). This work deals with making of holes on glass fiber reinforced polymer composite material using a newly designed nozzle with and without internal thread. The effect of jet pressure (P), stand-off distance (L), nozzle diameter (D), and abrasive size (S) on surface roughness (Ra) for two different nozzles was examined. The experimental result showed good surface finish on GFRP materials with the use of newly designed nozzle with an internal thread.