An investigation on surface roughness of granite machined by abrasive waterjet

Bulletin of Materials Science (Impact Factor: 0.58). 01/2011; 34(4):985-992. DOI: 10.1007/s12034-011-0226-x

ABSTRACT Abrasive waterjet (AWJ) cutting is an emerging technology which enables the shaping of practically all engineering materials.
However, AWJ cutting may cause roughness and waviness on the cut surface. This significantly affects the dimensional accuracy
of the machined part and the quality of surface finish. In this study, the surface roughness of three granites is experimentally
investigated for varying process parameters in abrasive waterjet. The philosophy of the Taguchi design is followed in the
experimental study. Effects of the control (process) factors on the surface roughness are presented in terms of the mean of
means responses. Additionally, the data obtained are evaluated statistically using the analysis of variance (ANOVA) to determine
significant process parameters affecting the surface roughness. Furthermore, effects of the material properties on the surface
roughness are assessed. It was statistically found that the water pressure and the abrasive flow rate are the most significant
factors influencing the surface roughness of granites. Additionally, a consistent relationship between the material grain
size and surface roughness of the granites was observed.

KeywordsAbrasive waterjet–granite–grain size–surface roughness

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