Preparation and properties of TiB₂/AlSi10Mg composite powders used for selective laser melting

TiB₂/AlSi10Mg composite powders used for selective laser melting were prepared by high-energy ball milling and plasma spheroidization, using the AlSi10Mg powders and high purity TiB₂ powders as the raw materials prepared by gas atomization. The microstructure and properties of TiB₂/AlSi10Mg composite powders before and after plasma spheroidization were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), laser particle size analyzer, and UV-visible spectrophotometer. The results show that the plasma spheroidization TiB₂/AlSi10Mg composite powders have the excellent sphericity and the uniform particle size distribution. Moreover, the chemical reactions between TiB₂ and Al may form the Al₃Ti phases, which can obtain the metallurgical bonding interface and improve the bonding strength. The core-shell structure of the composite powders is similar to that of TiB₂ coated with AlSi10Mg. The laser absorption rate of the powders is improved from 23.2% (AlSi10Mg) to 42.1% (TiB₂/AlSi10Mg).