EFFECTS OF THE SPRAY ANGLE ON SPLAT MORPHOLOGY DURING THERMAL SPRAYING

The effects of spray angle on the morphology of thermally sprayed part icles impinging on polished substrates have been studied by implementi ng several statistical tools (i.e., Gaussian analysis, Weibull distrib ution and the t-test). Nickel-based alloy (Astroloy) particles were va cuum plasma-sprayed onto copper plates at normal (i.e., 90 degrees) an d several off-normal spray angles (i.e., 75, 60, 45 and 30 degrees). D ifferent geometric shape factors (i.e., referring to an equivalent dia meter, elongation factor and degree of splashing) were determined usin g image analysis. The spray angle had a strong effect on these geometr ic properties, in particular on the elongation factor of the shapes.