Abstract
The quality of thermal sprayed coatings greatly depends on the individual flattened splats. Generally they are characterized by two main factors, flattening ratio and splat profile. The flattening ratio is specified straightforward, but it is difficult what factor should be selected from the various properties for the splat profiles. Fractal geometry is introduced to the profile evaluation of the splats which are formed by the free-fall metal droplets and by the alumina coatings using plasma spraying method. The fractal dimension of each splat was measured by SIA (Slit Island Analysis) technique which measures the ratio of area to contour length of the island appeared on the horizontally sliced plane of the splat. The obtained fractal dimension was related to with Re and We numbers in a bi-linear form, which is the same characteristics as the unevenness ratio obtained previously. It was concluded that fractal dimension is an effective measure to evaluate the splat profile.
