Effects of Electromagnetic Stirring, Shearing, and Extrusion on TiB₂ and TiAl₃ Particles in Al–5Ti–1B(wt.%) Alloy

Abstract

Electromagnetic stirring induced metal flow and led to homogenous dispersion of TiAl₃ particles. Fragmentation mechanism induced by electromagnetic stirring also contributed to TiAl₃ particle refining. TiAl₃ particle size decreased with the increases of stirring temperature and time. Shearing force among different melt layers under the shear action of roll in the roll-shoe gap increased with the decrease of casting temperature and the increase of melt viscosity, and the fragmentation of TiAl₃ phase became obvious correspondingly. Under the optimal process parameters, Al–5Ti–1B(wt.%) alloy wire with excellent inner microstructure and high surface quality was produced. The average sizes of TiAl₃ are less than 20 µm, and TiB₂ phases are less than 0.5 µm, respectively. Al–5Ti–1B(wt.%) alloy wire manufactured by present method has a high refining ability on pure aluminum and an excellent ability of refining effectiveness.

Keywords:

• Al–5Ti–1B(wt.%)
• Aluminum
• Casting
• Electromagnetic
• Extrusion
• Microstructure
• Refiner
• Shear