Evolution of (Ti, V) Compounds in the Al-Ti-V-B System and the Refinement Performance Thereof

Abstract

This study utilizes aluminum and titanium chips as raw materials and employs different boron sources in combination with melt reaction technology to successfully develop an innovative Al-2.5Ti-2.5 V-1B grain refiner. Experimental results indicate that the addition of V element enhances the formation of (Ti, V)Al₃ and (Ti, V)B₂ phases. When Al-3B is used as the B source, the (Ti, V)Al₃ phase displays long needle-like morphologies; in contrast, using KBF₄ as the B source results in the formation of short stick-like and small block-like structures. Among these B sources, the refiner containing Al-3B shows a more significant refinement effect. When 0.6% of this refiner is added to Al-7Si alloy at 760°C for a refining duration of 10 min, it significantly reduces the grain size from 1659 ± 83 µm to 388 ± 19 µm. Additionally, only a minimal increase in grain size is observed after 70 min, demonstrating its excellent resistance to anti-fading. This research advances the use of metal chips in producing effective grain refiners to counteract silicon poisoning in aluminum alloys.