Stabilities,mechanical and thermodynamic properties of 87 intermetallics in Al-RE binary system were studied by first-principles based on density functional theory(DFT).The results show that the calculated stabilities...Stabilities,mechanical and thermodynamic properties of 87 intermetallics in Al-RE binary system were studied by first-principles based on density functional theory(DFT).The results show that the calculated stabilities at T=0 K are in good agreement with experimental values.Al2 RE intermetallics exhibit the best stability in Al-RE binary compounds;and the stabilities in descending order are Al2 RE,Al3 RE,AlRE,Al11RE_(3),AlRE2 and AlRE_(3).The calculated Al-RE intermetallics possess mechanical stabilities.The hardness and strength of the most Al-RE intermetallics are greater than pure aluminum except AlCe,AlPr,AlEu and AlYb.The hardness and strength in descending order are Al11RE_(3),Al3 RE,Al2 RE and AIRE.Part of AlRE intermetallics exhibit ductility;the others are brittle.The heat capacities of Al-RE intermetallics in ascending order are Al-Sc,Al-Y,Al-lanthanides.On the contrary,the coefficient of thermal expansion(CTE)in ascending order is Al-lanthanides,Al-Y and Al-Sc.展开更多
文摘Stabilities,mechanical and thermodynamic properties of 87 intermetallics in Al-RE binary system were studied by first-principles based on density functional theory(DFT).The results show that the calculated stabilities at T=0 K are in good agreement with experimental values.Al2 RE intermetallics exhibit the best stability in Al-RE binary compounds;and the stabilities in descending order are Al2 RE,Al3 RE,AlRE,Al11RE_(3),AlRE2 and AlRE_(3).The calculated Al-RE intermetallics possess mechanical stabilities.The hardness and strength of the most Al-RE intermetallics are greater than pure aluminum except AlCe,AlPr,AlEu and AlYb.The hardness and strength in descending order are Al11RE_(3),Al3 RE,Al2 RE and AIRE.Part of AlRE intermetallics exhibit ductility;the others are brittle.The heat capacities of Al-RE intermetallics in ascending order are Al-Sc,Al-Y,Al-lanthanides.On the contrary,the coefficient of thermal expansion(CTE)in ascending order is Al-lanthanides,Al-Y and Al-Sc.
