Molecular-Dynamical Investigation of Thermomechanical Properties of Spherical Solid and Hollow Nickel Nanopowder during Laser Additive Manufacturing Process

Abstract

Molecular dynamics (MD) simulation with the embedded-atom method (EAM)/alloy potential is used to investigate the property of the nanoscale hollow spherical Nickel (Ni) powder during the laser additive manufacturing (AM) process. The thermomechanical properties of the Ni nanopowder is also explored (1) at room temperature and (2) from room temperature to the melting temperature during laser AM of powder bed fusion. As a result, the optimum parameters for the laser AM process are proposed. The optimal coalescence temperature of the nanoscale hollow spherical Ni powder is in the range between 980 and 1421K, while the melting temperature is in the range between 1320 and 1470 K. The coalescence and melting temperatures are lower than the melting point of Ni (1728 K).