Simulation of deformation and growth during surfacing of aluminum bronze nanograins

Abstract

In additive manufacturing, it is important to determine the technological and structural factors that control the crystallization process and specify the required structure of the product. The crystallization structure is affected by the parameters of the starting material and the crystallization conditions. Using the orientation of the grains of the substrate, which is formed after electron-beam surfacing of aluminum bronze, the modeling parameters were set by the molecular dynamics simulation. The process of deformation of three adjacent grains under constrained conditions and structural changes in the process of interaction with a melt drop and subsequent crystallization were considered. An analysis of grain deformation made it possible to reveal the role of geometric shear stress concentrators and to determine the significance of constrained conditions for deformation of polycrystal grains. It has been established that under the influence of a drop of melt, stacking faults are the least thermally stable, and twins are the most stable. The crystallographic orientation of the crystallizing grains coincides with the orientation of the substrate grains. During crystallization, columnar grains continue to grow, in which stacking faults and twins are formed.