Abstract

Refractory rare metal tungsten (W) material has significant applications in many key industrial areas due to its superior properties. However, how to fabricate high-performance W component with high relative density, complicated geometry, and desired structure is still challenging. Many issues need to be further explored and clarified. Under this circumstance, comprehensive multi-scale numerical investigations were conducted on the EBSM (electron beam selective melting) additive manufacturing (AM, also called 3D printing) of pure W components with lattice structures using coupled DEM-CFD (discrete element methodcomputational fluid dynamics) model. The material parameters of pure W powders with continuous size distributions utilized in actual AM production were firstly calibrated and input into DEM model for parametric study on powder spreading. Then, the EBSM 3D printing of the spread powder bed of W was simulated by CFD. In the whole process, the cumulative and cooperative effects of the powder layer and the printed area on the whole printing process were systematically discussed. Meanwhile, the underlying mechanisms were analyzed and identified. On this basis, corresponding physical experiments were carried out. The obtained highlighted results can be of both theoretical and practical significances for the design and additive manufacturing of high-performance W components in real process.