Microstructure and refinement mechanism of TiB₂/TiAl₃ in remelted Al-5Ti-1B system

Abstract

In this work, we propose a new method (by remelting Al-5Ti-1B) to investigate the grain refinement mechansim. It is found that the morphology and size of TiAl3 phase had little effect on the grain refinement of pure Al. Therefore, further experimental studies were carried out to understand the potency of TiB2 particles. The high-resolution transmission electron microscopy (HRTEM) observation has confirmed the existence of an atomic layer on the surface of (0001) TiB2, which is possibly a two-dimensional (2D) (1-12) TiAl3. Crystallographic study indicates that it is a more suitable nucleation sites for α-Al than other particles. The TiB2 particle with TiAl3 2D acts as the best effective nucleation sites for α-Al.

Thermomechanical Control of Microstructure and Precipitation in Vanadium Microalloyed Steel: Influence of Finish Rolling and Coiling Temperatures

“…Therefore, the FRT is conducive to the formation of AF and the refinement of the ferrite grains, thereby improving both the strength and toughness of the steel. [ 46 ]…”

“…Therefore, the FRT is conducive to the formation of AF and the refinement of the ferrite grains, thereby improving both the strength and toughness of the steel. [46] Figure 5 shows the microstructure of AF after TMCP with FRTs varying from 805 to 850 °C at a CT of 550 °C observed under TEM. As shown, the morphology of the microstructures is needle-like or nonequiaxial lath like, with a relatively large aspect ratio and a width between ≈0.2 and ≈0.9 μm, which is a typical feature of AF.…”

Optimization Studies of AC4CH Material in the Cylinder Block of a Diesel Engine Application

“…Therefore, the amount of TiAl3 and AlB2 that could refine the grains might be lower. In other words, although the size of the grains became smaller with no grain modification, it seems that TiAl3 and AlB2 do not solute [29]. Further, when 0.1% Al-5Ti-1B master alloy was added, the sizes of the grains were in the range of 600-850 μm, which was generally large, Figure 9 shows the results of the addition of the Al-5Ti-1B master alloy, which has been widely used to refine grains.…”

Functional and Environmental Advantage of Cleaning Ti5B1 Master Alloy

“…Producing higher quality master alloy for grain refinement often requires only stricter quality control or minimal changes in the production process without requirements for high capital costs. Tight monitoring of the pro duction process to generate a larger number of finer TiB 2 particles and prevent intrusion of refractory oxides results in the production of higher quality master alloys [40]. Aside from higher market value, such a master alloy will extend the service time of produced parts and allo w easier recycling at the end of its lifetime.…”