The Influence of the Fusion State of the Particles during the Simultaneous Impact on an Oxidized Substrate in the Presence of Asperities

Abstract

The surface areas of the materials are generally the most vulnerable parts since they are directly exposed to different stresses such as wear, fatigue, and corrosion. On the other hand, the successive impact of the droplets finds numerous applications in additive manufacturing technologies such as 3D printing and liquid metal projection. The lamella state formed by the impact and spreading of the first particle represents the target for the second; however, its molten state or fragmented state, bouncing or a slide, interacts thermally and dynamically to allow or not allow stacking. The deposition, deformation, and solidification of the droplets are the constituent steps of the process which determine the final result, as the topography of the substrate not only conditions the mechanical adhesion of the drop to the substrate but also affects the wettability of the surfaces. The objective of this work was to model by numerical simulation the impact of successive and simultaneous droplets with solidification and simultaneous deformation in the presence of an oxide layer on the substrate, which presents different topography, in order to fix the knowledge on the behavior of the impact, the spreading, or the splashing with solidification. However, a peak diameter greater than 5% of the particle diameter causes the formation of concave roughness which directly infects the mechanical adhering and subsequently the formation of an ordinary lamella.