摘要
Al-V-B master alloy is promising for refining Al-Si alloys,yet its optimal composition with superior efficacy remains to be explored.In this work,the evolution of refining phases in the Al-10 Si/Al-V-B system with different V:B ratios was evaluated by thermodynamic calculations,based on which the Al-V-B refiners with V:B=1:1 and 5:1 were designed.Refining trails demonstrated that they could significantly reduce the grain size of Al-10 Si(wt.%)alloy from 1736 to 184-245μm with industrial addition amount.Detailed examinations results clarify that when V:B ratio is 1:1 the nucleation particle is(V,Al)B_(2),which has a VB_(2)-AlB_(2) core-shell structure and therefore presents the nucleation capability as AlB_(2) particle.When V:B ratio is as high as 5:1,the nucleation particle is pure VB_(2).Density functional theory(DFT)calculation indicates that(0001)VB_(2)/(111)α-Al interface has the lowest interfacial energy such that highest nucleation potency among other types of diboride/α-Al interfaces under consideration.The outcomes of this work provide fundamental guidance to develop superior V-B based refiners for Al-Si alloys.
基金
financially supported by the National Natural Science Foundation of China(No.51871138)
the Science and Technology Commission of Shanghai Municipality(No.19010500400)
the"111"projects(No.D16002)。
作者简介
Chenxi Zhao,contributed equally to this work;Yang Li,contributed equally to this work;Corresponding author at:Qian Li,State Key Laboratory of Advanced Special Steels,Shanghai Key Laboratory of Advanced Ferrometallurgy,School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China.E-mail address:shuliqian@shu.edu.cn。
