Transition behavior of the splat pattern of Ni sprayed particles on flat substrate was investigated. From both Auger analysis of the splash splat and SEM observation of splash splat on Au coated substrate, it was confirmed that the splashing was formed by not flowing on the substrate surface from impingement center to periphery, but jetting away from central disk. The observation result of etched splat surface revealed that the bottom part of the central disk of the splash splat solidified quite rapidly just after the impingement on the cold substrate. From the fact that the splash splat pattern was recognized only in the direction perpendicular to the scratching in the splat on the unidirectionally scratched substrate, it was confirmed that the splashing was caused by stumbling due to some kinds of deterrent to the liquid flow, such as poor wettability at the flow tip or initial rapid solidification of the splat. The drastic change of the splat pattern nearby the transition temperature seems to occur when the We number of the liquid flow coincide with some critical value.

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