Molecular dynamics simulation of ultrasound-assisted 3D printing of aluminum matrix composites

Additive manufacturing technology, with its characteristics of no mold and short production cycle, provides a new scheme for the machining and manufacturing of high performance and difficult material parts. However, the forming process of additive manufacturing is non-equilibrium solidification, which is easy to form uneven microstructure and reduce the mechanical properties of the parts. Special energy field assisted forming technology has great potential in improving the manufacturing problems of high-strength difficult-to-process materials. In recent years, it has been continuously applied to additive manufacturing to improve the microstructure and properties of parts. Ultrasonic assistant is an important method to reduce the residual stress in the additive manufacturing process, and its scientific principle is still a frontier scientific issue. Therefore, this paper uses molecular dynamics (MD) method to study the influence of ultrasonic assistance on residual stress in additive manufacturing process. In this paper, the process of ultrasound-assisted 3D printing of graphene reinforced aluminum (Al) matrix composites was simulated by MD method. The effects of ultrasonic aid on grain size, orientation and dislocation in the composites were analyzed, and the mechanism of ultrasonic aid reduction of residual stress was revealed, which provided theoretical guidance for ultrasonic aid additive manufacturing process.