Abstract
In this work,Zn microalloyed with Al,Mn,Cu,Ag and Li was cast,annealed and extruded.The results showed that addition of multiple trace elements causes significant change in the microstructures,me-chanical properties and corrosion behavior of Zn-0.1Al-0.1Mn-0.1Cu-0.1Ag(1ZM),Zn-0.1Al-0.1Mn-0.1Cu-0.1 Ag-0.1 Li(2ZM-0.1Li)and Zn-0.1Al-0.1Mn-0.1Cu-0.1Ag-0.35Li(3ZM-0.35Li)alloys.Two ternary phases with the approximate compositions of Al13Mn3Zn34 and Al10MnZn89 phases are formed in the casting and annealing processes of these alloys,respectively.Wavy β-LiZn4 lamellae that have not been extensively reported are precipitated from the primary Zn dendrites in the casting process of ZM-0.35Li alloy.Also,Zn laths are precipitated from the eutectic β-LiZn4 phase in the annealing process of ZM-0.35Li alloy.The above-mentioned phases are crushed or elongated in the as-extruded alloys,which play an important role in improving the strength of the alloys.All the as-extruded alloys have typical(0001)basal tex-ture,accompanied with relatively low{0001}<11(2)0>slip and high{10(1)2}<10(1)(1)>twinning Schmid factors,which are advantageous and disadvantageous to the strength enhancement of the alloys,respec-tively.All the as-cast alloys exhibit poor mechanical properties,especially low ductility.The as-extruded ZM alloy exhibits ultrahigh ductility,with an elongation of up to 82.2％±2.94％.The as-extruded ZM-0.35Li alloy shows the best comprehensive mechanical properties,with yield strength,ultimate tensile strength,elongation and hardness of 380±1.6 MPa,449±7.4 MPa,62.3％±4.63％and 98±1.4 HV,respectively.Electrochemical corrosion rates of the ZM,ZM-0.lLi and ZM-0.35Li alloys are 0.241±0.004,0.206±0.006 and 0.189±0.008 mm/year,respectively.In vitro immersion corrosion rates(after 26 d in SBF solution)of them are 0.134±0.005,0.125±0.004 and 0.121±0.003 mm/year,respectively.The as-extruded ZM-0.35Li alloy exhibits the best corrosion resistance.
基金项目
National Natural Science Foundation of China(51874092)
National Natural Science Foundation of China(51690161)
Fundamental Research Funds for the Central Universities(N180905009)
NETL
NSTL
万方数据