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 dif...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.展开更多
目的:对白骨壤果实中微量元素进行测定分析。方法:采用微波消解-电感耦合等离子体发射光谱法(微波消解-ICP-OES法)测定白骨壤果实中Zn、Ni、Fe、Mg、Mn、Cr、Al、V、Cd、As、Cu、Pb、Ba、B共14种微量元素含量。使用电感耦合等离子...目的:对白骨壤果实中微量元素进行测定分析。方法:采用微波消解-电感耦合等离子体发射光谱法(微波消解-ICP-OES法)测定白骨壤果实中Zn、Ni、Fe、Mg、Mn、Cr、Al、V、Cd、As、Cu、Pb、Ba、B共14种微量元素含量。使用电感耦合等离子体发射光谱仪,发射功率1.2 k W,等离子气流量15 L·min^-1,辅助气流量1.5 L·min^-1,雾化气压200 k Pa,泵速15 r·min^-1,进样延迟时间为30 s。结果:白骨壤果实中含有丰富的微量元素Mg、Al、Fe、Mn等,而Cd和As含量极低或未检出。精密度试验的RSD为0.8%-3.6%,加标回收率为96.2%-102.4%。结论:建立的微波消解-ICP-OES分析方法可测定白骨壤果实中多种微量元素,同时为测定其他药材中微量元素的测定提供参考和理论依据。展开更多
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)。
文摘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.
文摘目的:对白骨壤果实中微量元素进行测定分析。方法:采用微波消解-电感耦合等离子体发射光谱法(微波消解-ICP-OES法)测定白骨壤果实中Zn、Ni、Fe、Mg、Mn、Cr、Al、V、Cd、As、Cu、Pb、Ba、B共14种微量元素含量。使用电感耦合等离子体发射光谱仪,发射功率1.2 k W,等离子气流量15 L·min^-1,辅助气流量1.5 L·min^-1,雾化气压200 k Pa,泵速15 r·min^-1,进样延迟时间为30 s。结果:白骨壤果实中含有丰富的微量元素Mg、Al、Fe、Mn等,而Cd和As含量极低或未检出。精密度试验的RSD为0.8%-3.6%,加标回收率为96.2%-102.4%。结论:建立的微波消解-ICP-OES分析方法可测定白骨壤果实中多种微量元素,同时为测定其他药材中微量元素的测定提供参考和理论依据。