Microstructures and Mechanical Properties of Al₃Ti/Al Composites Produced In Situ by High Shearing Technology

Abstract

Due to its low density, high strength, and stiffness the intermetallic phase Al 3 Ti is a good candidate as reinforcement for Al alloys. In this work, in situ Al 3 Ti particle reinforced Al composites are fabricated from Ti particles and Al melt via melt stirring with a high shearing mixer. Microstructure and mechanical properties are investigated. The results indicate that, owing to the high shearing effect and intensive macroscopic flow of the melt, reinforced particles are distributed homogeneously on the microscopic and macroscopic scale. Furthermore, Al 3 Ti particles are proved to be effective nuclei for heterogeneous nucleation of α-Al, thus the grain size of the Al matrix is significantly decreased. As a result of the fine grains and the uniform distribution of Al 3 Ti particles, E-modulus, yield, and tensile strength of the composites are enhanced.

A Comparative Study of Grain Refining of Al-(7–17%) Si Cast Alloys Using Al-10% Ti and Al-4% B Master Alloys

“…Mechanical stirring was particularly important for this system due to the difference between the density of the used alloy (2685 kg/m 3 ) and that of the Al 3 Ti intermetallics (3368 kg/m 3 ) [ 19 ]. To examine the effect of holding time at the required temperature, mechanical stirring was continued until the liquid metal was poured into the graphite mold [ 20 ] as shown in Figure 4 .…”

Effect of Waste Titanium Chips Addition Into the Aluminum Alloys on Their Microstructure

“…Before experiments also utilized K2TiF6 salt-metal reactions to produce 5 vol. % Al3Ti/A356 composites [15]. They also investigated the effects of T6 heat treatment and Sr modification on the microstructural and mechanical properties of the composites.…”

In situ Al 3 Ti/Al composites fabricated by high shear technology: microstructure and mechanical properties

“…Moreover, the strong interface bonding between the reinforcing particle and the Al matrix is also attractive. In addition, the Al 3 Ti phase has been proved to be an effective grain refiner for the Al matrix due to the similar crystal structures of Al 3 Ti phase and Al [11]. Liu et al [12] applied the direction reaction between Ti powder and Al melt to prepare Al 3 Ti/Al composites.…”

“…Moreover, it can also generate intensive macroscopic melt flow to distribute the reinforcing particles homogeneously within the final castings. Further information about the application of the HST in preparing particle reinforced metal matrix composites (PMMCs) [11,16] and grain refinement [17] have been reported.…”