Abstract
Copper splats are deposited on the flat stainless steel surface at the ambient and preheated conditions. The splashing occurs as the splats are deposited at an ambient atmosphere. The characteristics of the splashing occurring at different splat regions during spreading of the droplet are examined. The splashing can be classified into two types according to the splashing mechanisms. At the surrounding region of the splat larger than flattening ratio about 1.5 to 2, the radial splashing takes place by jetting-away of splat materials, which leads to the formation of a splat with a reduced diameter. At the central area of the reduced splat, the upward splashing occurs through the blowing up of the top surface layer which results from the high pressure of gas bubbles. At the preheated condition which can remove surface adsorbates, no evident splashing occurs under the normal spray conditions. Two types of splashing can be explained by the gases evolved through evaporation of the adsorbates resulting from the heating of the high temperature droplet. The spreading of the droplet involved in the wave urging flow is presented.
