Microstructure and Mechanical Properties of Ti6Al4V Alloy Modified and Reinforced by In Situ Ti5Si3/Ti Composite Ribbon Inoculants

Abstract

This paper deals with a novel fabrication method (a vacuum rapid solidification technique) to prepare in situ Ti 5 Si 3 /Ti composite ribbon as inoculants to modify Ti6Al4V alloy to obtain titanium matrix composites (TMCs). Microstructure and morphology observations showed that the grain size of the TMCs was refined as the volume fraction of inoculants increased. The grain size of the TMCs can be refined from a grade of 650 µm to about 110 µm with a very small refiner adding ratio of 0.6% in weight. Thereafter, the mechanical properties of the TMCs, including their tensile strength, microhardness, impact properties, and resistant properties were improved obviously by adding the ribbon inoculants. The excellent grain refining and reinforcement effect can be attributed to the nano-sized Ti 5 Si 3 refiner particles distributed homogeneously in the matrix, the well-banded particle/matrix interface, and the good wettability between the Ti 5 Si 3 particles in inoculants and the Ti6Al4V alloy melt, which are benefit for the heterogeneous nucleation of the TMCs during solidification.

Report on use of Inoculants in Missile Application Alloys

“…The TiN particle additions reduced the beta grain size and modified them from columnar to equiaxed grains with an average size of 300 mu m. The ZrN powder was not effective at the low levels studied. Additional research involving this alloy used a vacuum rapid solidification technique to prepare in situ Ti5Si3/Ti composite ribbons [124]. The ribbons were used as inoculants in Ti-6Al-4V to obtain titanium matrix composites (TMCs).…”

The Effect of Zirconium and Yttrium Oxide on the Microstructure and Mechanical Properties of Ti-Si-Zr Based Composites

“…[7,8] At high temperatures, its most stable state, Ti 5 Si 3 , acts as reinforcement in the α -Ti matrix phase. [9][10][11] The addition of metallic elements to the Ti-Si system also increases the performance of the composite materials significantly through the formation of M x Si y -type compounds. [12] The M x Si y -type compounds change the structure and phase composition of the composite through improved grain refinements, reaction efficiency, density, and porosity.…”

Fabrication and Mechanical Behavior of Ex Situ Mg-Based Bulk Metallic Glass Matrix Composite Reinforced with Electroless Cu-Coated SiC Particles

“…However, these additives are generally heavy phases, and will therefore increase the density of the composite, which is not conducive to the lightweight development of composite materials. Furthermore, the introduction of soft or plastic phases will decrease the yield strength [ 7 ] and reduce the competitiveness of BMGs with respect to other high-strength materials such as steels [ 13 ], titanium alloys [ 14 , 15 , 16 ] and high entropy alloys [ 17 , 18 ].…”