Abstract
Grain refinement of Al and Al alloys during the solidification remains a long-term challenge.Here we report a general strategy for efficient grain refinement through instantaneously in-situ forming abundant nanoparticles with concentrated size distribution.The Al-Zn-Mg-Cu alloy and commercial purity Al are respectively refined by using this proposed strategy and the traditional refinement method(adding Al-Ti-B alloy into Al melt),and the experimental and numerical results indicate that the TiB2 nanoparticles instantaneously form in the Al melt during the in-situ refinement process.Compared to the traditional refinement treatment method,the new approach not only can promote the high number density of the nucleation sites and narrow their size distribution,but also tremendously attenuates the agglomeration and settlement of the heterogeneous nucleation sites.It exhibits much better grain refinement ability and inhibits the decline of the grain refinement efficiency.This approach may have broad application prospect not only for the grain refinement of Al and Al alloys,but also for the grain refinement of other alloy systems,e.g.steel,magnesium,copper,and so on.
维普
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