Abstract
Al-Ti-B type master alloys are routinely added into aluminum for a grain refinement purpose. However, a consensus about the mechanism of grain refinement is still yet to reach. This work is aiming at further understanding the grain refinement mechanism through studying the stability of TiB2 in pure aluminum and TiB2/Al3Ti interfaces in aluminum by transmission electron microscopic (TEM) techniques. It is found that TiB2 reacts with aluminum forming (Ti,Al)B2 solid solution and releasing titanium into aluminum. A crystallographic orientation relationship exists between TiB2 and Al3Ti in Al-Ti-B alloys. A dynamic nucleation theory for the grain refinement is therefore proposed as a dynamic Al3Ti layer in the thickness of a couple of atoms existing on the surface of (Ti,Al)B2 and being responsible for nucleating aluminum grains.
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Wang, X., Han, Q. (2016). Grain Refinement Mechanism of Aluminum by Al-Ti-B Master Alloys. In: Williams, E. (eds) Light Metals 2016. Springer, Cham. https://doi.org/10.1007/978-3-319-48251-4_32
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DOI: https://doi.org/10.1007/978-3-319-48251-4_32
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48615-4
Online ISBN: 978-3-319-48251-4
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