Microblasting characteristics of jewellery models built using stereolithography apparatus (SLA)

Abstract

This paper describes an investigation of the effect of the microblasting process on the surface finish of jewellery models built using stereolithography apparatus (SLA). The layering process of SLA results in visible steps on the model surface. The investigation aims to determine the significant operating parameters of the microblaster deburring process that affect the surface roughness of the SLA jewellery model, to set a practicable range for these parameters for effective deburring and establish the optimum parameters for the best surface finish. A ring model based on the British Standards 28653: 1993 is designed using the Pro-Engineer software. The experimental strategy applies techniques including the full factorial and Yates' method together with the analysis of variance on the deburred samples. The surface roughness of the ring models before and after the deburring process are then measured with a Form Talysurf surface roughness measuring machine. The information obtained is used to identify the parameters for further study. Parameters identified are different nozzle types, blasting time and pressure variation. These parameters are tested for their optimum settings and the microblasting process is found to significantly improve the surface finish by approximately 30% on both the curvature and flat features of the ring model.