The effects of the co-addition of Ni and Zn on the microstructure and mechanical properties of the extruded Mg-6.84Y2.45Cu(MYC,wt%)alloy were researched.Results show that the as-cast Mg-6.79Y-1.21Cu-1.12Ni-1.25Zn(MYCN...The effects of the co-addition of Ni and Zn on the microstructure and mechanical properties of the extruded Mg-6.84Y2.45Cu(MYC,wt%)alloy were researched.Results show that the as-cast Mg-6.79Y-1.21Cu-1.12Ni-1.25Zn(MYCNZ,wt%)alloy consists of theα-Mg,a few Y-rich phases,lamellar 18R-long period stacking ordered(LPSO)phase,and granular Mg_(2)(Cu,Ni,Zn)phase.After the homogenization process,phase transformation occurs in MYCNZ alloy.Some 18R-LPSO phases at the grain boundary are transformed into the thin striped 14H-LPSO phase in the grains.After extrusion,the amount,morphology,and distribution of the second phase are changed,and the grain size of the extruded MYCNZ alloy is significantly reduced to approximately 2.62µm.Additionally,a weaker basal texture is formed in the extruded MYCNZ alloy.The tensile results indicate that the co-addition of Ni and Zn significantly enhances the tensile strength of the extruded MYC alloy while maintaining good ductility.The tensile yield strength(σ_(0.2)),ultimate tensile strength(σ_(b)),and elongation to failure(ε_(L))of the extruded MYCNZ alloy are 266.9 MPa,299.8 MPa,and 20.1%,respectively.This alloy has a good strength-plastic synergistic effect.The excellent tensile strength of the extruded MYCNZ alloy at room temperature is mainly due to grain refinement and the second phase strengthening effect,and its outstanding ductility is ascribed to the texture weakening and activation of non-basal slips.展开更多
The corrosion mechanism of Mg-Y alloys in 3.5% NaCl solution was investigated by electrochemical testing and SEM observation. The electrochemical results indicated that the corrosion potential of Mg-Y alloys in 3.5% N...The corrosion mechanism of Mg-Y alloys in 3.5% NaCl solution was investigated by electrochemical testing and SEM observation. The electrochemical results indicated that the corrosion potential of Mg-Y alloys in 3.5% NaCl solution increased with the increase of Y addition. The corrosion rate increased with the increase of Y addition because of the increase of Mg24Y5 intermetallic amounts. The corrosion gradually deteriorated with the increase of immersion time. The corrosion morphologies of the alloys were general corrosion for Mg-0.25Y and pitting corrosion for Mg-8Y and Mg-15Y, respectively. The main solid corrosion products were Mg(OH)2 and Mg2(OH)3C1·4H2O.展开更多
基金Major Science and Technology Project of Gansu Province(22ZD6GA008)National Natural Science Foundation of China(52261027,51961021,52001152)+2 种基金Open Project of State Key Laboratory for Mechanical Behavior of Materials(20192102)Undergraduate Innovation and Entrepreneurship Training Program(DC20231188,DC20231482,DC20231558,DC20231469,DC20231441)Supported by Sinoma Institute of Materials Research(Guang Zhou)Co.,Ltd(SIMR)。
文摘The effects of the co-addition of Ni and Zn on the microstructure and mechanical properties of the extruded Mg-6.84Y2.45Cu(MYC,wt%)alloy were researched.Results show that the as-cast Mg-6.79Y-1.21Cu-1.12Ni-1.25Zn(MYCNZ,wt%)alloy consists of theα-Mg,a few Y-rich phases,lamellar 18R-long period stacking ordered(LPSO)phase,and granular Mg_(2)(Cu,Ni,Zn)phase.After the homogenization process,phase transformation occurs in MYCNZ alloy.Some 18R-LPSO phases at the grain boundary are transformed into the thin striped 14H-LPSO phase in the grains.After extrusion,the amount,morphology,and distribution of the second phase are changed,and the grain size of the extruded MYCNZ alloy is significantly reduced to approximately 2.62µm.Additionally,a weaker basal texture is formed in the extruded MYCNZ alloy.The tensile results indicate that the co-addition of Ni and Zn significantly enhances the tensile strength of the extruded MYC alloy while maintaining good ductility.The tensile yield strength(σ_(0.2)),ultimate tensile strength(σ_(b)),and elongation to failure(ε_(L))of the extruded MYCNZ alloy are 266.9 MPa,299.8 MPa,and 20.1%,respectively.This alloy has a good strength-plastic synergistic effect.The excellent tensile strength of the extruded MYCNZ alloy at room temperature is mainly due to grain refinement and the second phase strengthening effect,and its outstanding ductility is ascribed to the texture weakening and activation of non-basal slips.
基金Project(2011BAE22B01)supported by the National Key Technology R&D Program of Chinasupported by Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts which is jointly built by Beijing North Vehicle Group Corporation and University of Science and Technology Beijing
文摘The corrosion mechanism of Mg-Y alloys in 3.5% NaCl solution was investigated by electrochemical testing and SEM observation. The electrochemical results indicated that the corrosion potential of Mg-Y alloys in 3.5% NaCl solution increased with the increase of Y addition. The corrosion rate increased with the increase of Y addition because of the increase of Mg24Y5 intermetallic amounts. The corrosion gradually deteriorated with the increase of immersion time. The corrosion morphologies of the alloys were general corrosion for Mg-0.25Y and pitting corrosion for Mg-8Y and Mg-15Y, respectively. The main solid corrosion products were Mg(OH)2 and Mg2(OH)3C1·4H2O.