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In this study, TiB+La2O3/Ti-6Al-4V composites were successfully prepared by in-situ reaction using selective laser melting technology. The effect of LaB6 content on the fabrication quality, microstructure evolution and mechanical properties of the composite samples was investigated. The results show that the relative density of the sample gradually decreases from 98.56% to 96.57% as the LaB6 content increases. During the printing process, the microstructure of the sample gradually aggregates due to the influence of the Marangoni flow and grows from a discrete needle-like structure to a dendritic structure with increasing LaB6 content, eventually developing into a cell-like structure. After adding LaB6 to titanium alloys, the hardness, wear resistance, and tensile strength of the composite are enhanced due to grain refinement strengthening, dispersion strengthening, and solid solution strengthening, while the plasticity of the material is lost. The 3wt% LaB6 sample has the most significant strengthening effect. Compared to the 0wt% LaB6 sample, the hardness is increased by 35.71%, the wear volume is reduced by 47.5%, the tensile strength is increased by 14.5%, and the elongation after fracture is reduced by 37.2%. The 0.5wt% LaB6 sample has the best formability and is most suitable for production practice. |
