This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategi...This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic calculations.Bulk CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum strain.The incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific strength.Synergistic effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance strength.Detailed exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of CCAs.These methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.展开更多
Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy...Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy,and structural sectors.This investigation delves into the AlFexNiTiV_(40-x)(x=0,10,20,30,35,40;at%)CCAs,aiming to unlock the synergistic potential of BCC and L2_(1)phases.By conducting an in-depth analysis of microstructure,phase behavior,and mechanical properties,the intricate relationships between chemistry,structure,and properties are illuminated within this alloy system.The Al_(15)Fe_(35)Ni_(3)0Ti_(15)V_(5)alloy demonstrates remarkable mechanical properties,achieving a yield strength of 2140.9 MPa and ultimate compressive strength of 2699.7 MPa,primarily through solid solution strengthening and precipitation hardening.Notably,its low lattice mismatches and nanoprecipitate strengthening yield an impressive specific yield strength at 600℃(245.2 MPa(g·cm^(-3))^(-1)).Phase modulation achieves the synergistic optimization of specific strengths at both room and high temperatures in CCAs containing the L2_(1)phase,opening new avenues for designing advanced lightweight and high strength alloys for elevated-temperature applications.展开更多
基金financially supported by Guangdong Basic and Applied Basic Research Foundation (No. 2021A1515012626)Shenzhen Knowledge Innovation Plan-Fundamental Research (Discipline Distribution) (No. JCYJ20180507184623297)+1 种基金the National Natural Science Foundation of China (No.52301043)the Postdoctoral Research Startup Expenses of Shenzhen (No.NA25501001)。
文摘This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic calculations.Bulk CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum strain.The incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific strength.Synergistic effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance strength.Detailed exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of CCAs.These methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.
基金supported by the National Natural Science Foundation of China(Nos.52301043 and 51871077)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515012626),Shenzhen Knowledge Innovation Plan-Fundamental Research(Discipline Distribution)(No.JCYJ20180507184623297)+1 种基金Shenzhen Science and Technology Plan-Technology Innovation(No.KQJSCX20180328165656256)the Startup Foundation from Shenzhen(Nos.NA25501001,and NA11409005).
文摘Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy,and structural sectors.This investigation delves into the AlFexNiTiV_(40-x)(x=0,10,20,30,35,40;at%)CCAs,aiming to unlock the synergistic potential of BCC and L2_(1)phases.By conducting an in-depth analysis of microstructure,phase behavior,and mechanical properties,the intricate relationships between chemistry,structure,and properties are illuminated within this alloy system.The Al_(15)Fe_(35)Ni_(3)0Ti_(15)V_(5)alloy demonstrates remarkable mechanical properties,achieving a yield strength of 2140.9 MPa and ultimate compressive strength of 2699.7 MPa,primarily through solid solution strengthening and precipitation hardening.Notably,its low lattice mismatches and nanoprecipitate strengthening yield an impressive specific yield strength at 600℃(245.2 MPa(g·cm^(-3))^(-1)).Phase modulation achieves the synergistic optimization of specific strengths at both room and high temperatures in CCAs containing the L2_(1)phase,opening new avenues for designing advanced lightweight and high strength alloys for elevated-temperature applications.
