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TiB/Ti6Al4V composite was prepared using spark plasma sintering followed by bidirectional reaction hot rolling. The TiB whiskers were synthesized in situ during the rolling process, thereby preserving a relatively high structural integrity. TiB whiskers were distributed within the composite in three distinct locations: intragranular, intergranular, and transgranular distribution. After eight passes of vertical bidirectional reaction hot rolling, the average grain size of the matrix was refined to 1.36 μm, and the grains exhibited random crystallographic orientations. Tensile properties in different directions demonstrated high consistency, with a strength of 1220 MPa ± 30 MPa and an elongation of 8.0% ± 0.5%. The primary strengthening mechanisms in the composite included grain refinement, dislocation strengthening, and load transfer strengthening from the TiB. • Dense TiB 2 /Ti6Al4V billets were achieved via SPS. • A multi-pass bidirectional in-situ reaction hot rolling method was employed to prepare TiB/Ti6Al4V composite. • The TiB/Ti6Al4V composite showed consistent strength and ductility in all directions. [ABSTRACT FROM AUTHOR]

Abstract Al–Si–Mg alloys manipulated by in-situ synthesized nanoparticles have been prepared by casting method in this work. The addition of different contents of refiners promoted the obvious grain refinement of the Al–Si–Mg alloys. It was found that 0.10 wt% refiners addition caused a significant and efficient refinement on α-Al (from 1675 µm to 199 µm) and Mg 2 Si in the inoculated Al–Si–Mg alloys. The morphology of the eutectic Si in the inoculated Al–Si–Mg alloys transformed from needle-like structure to a fibrous one, and the mean size sharply decreased (from 26.56 µm to 11.89 µm) and increased a little with the increase of FeBSi amorphous refiners content. Tensile property tests showed that both strength and ductility of the alloys were improved by the addition of FeBSi amorphous refiners. The yield strength, tensile strength, fracture strain and elongation of the alloy inoculated with 0.10 wt% FeBSi amorphous refiners for 20 min were 226 MPa, 343 MPa, 18.4% and 16.7%, compared to those of the uninoculated alloy (170 MPa, 289 MPa, 13.7% and 12.2%), respectively. It was found that the Fe 2 B and Fe 3 Si nano-sized particles which were crystallized from FeBSi amorphous refiner contributed to the grain refinement of α-Al, resulting in higher strength. Moreover, grain refinement shortened the atomic diffusion distance and refines Mg 2 Si. The grain refinement and spheroidization of eutectic Si enhance uniform deformation during tension, and reduce the possibility of crack initiation and expansion, thus improving the plasticity. Graphical abstract fx1 Highlights • The inoculated Al–7Si–0.3Mg alloy appeared as 199 µm fine grains. • The inoculated alloy reached 226 MPa, 343 MPa, 18.4%(δ) and 16.7%(ε f). • This work achieved the refinement of α-Al and Mg 2 Si and the spheroidization of eutectic Si. • The Fe 2 B, Fe 3 Si had better lattice mismatch with α-Al and eutectic Si. [ABSTRACT FROM AUTHOR]