Selective laser melted TiB2/Ti6Al4V graded materials and first-principle calculations

Selective laser melting (SLM), as a rapidly developed layer-by-layer 3D printing technology, has been demonstrated that it can be used for additive manufacturing of multi-materials. In this work, TiB2/Ti6Al4V multi-materials were manufactured by SLM. The results showed that interfacial microstructures consisting of un-melted TiB2 powders, columnar TiB crystals, and acicular TiB crystals were formed in the molten pool. Meanwhile, a variation nanohardness was developed with chemical compositions at the interfacial regions, owing to an in-situ reaction of Ti and TiB2. The first-principle calculations were used to reveal the axial growth of TiB crystals as well as the different hardness of this system. (C) 2019 Elsevier B.V. All rights reserved.