The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-condit...The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-conditioned equations,the activity interaction coeffients between Ce and Al.Si,Ti and Fe alloying elements were determined.The equilibrium constant of the reaction 2[Ce]+3[O]=Ce_(2)O_(3)and the standard free energy of formation of Ce203 in liquid Cu were obtained at 1.200 C.展开更多
The thermodynamic properties of Cu-Ce-S and Cu-Y-S liquid solutions were studied by the chemical equilibrium technique at 1200℃. The equilibrium constants and the standard free energies of formation of CeS and YS wer...The thermodynamic properties of Cu-Ce-S and Cu-Y-S liquid solutions were studied by the chemical equilibrium technique at 1200℃. The equilibrium constants and the standard free energies of formation of CeS and YS were determined for the reactions: CeS=[Ce]+[S] and YS = [Y]+[S] . For the solution of Ce_(1) and Y_(l) in pure Cu according to the reactions: Ce_(1)= [Ce] and Y_(1)= [Y] , the standard free energies of solutions were obtained. The first order and second order interaction coefficients between solute elements as well as the activity coefficients γ_(Ce)~0 and γ_Y^0 in liquid Cu were also determined.展开更多
To obtain lightweight multicomponent magnesium alloys with high tensile strength,ductility,and stiffness,two extruded Mg_(92−5x)Al_(1.5+3x)Zn_(3)Cu_(3.5+x)Ce_(x)(x=0.5 and 1,labeled as C0.5 and C1)alloys were designed...To obtain lightweight multicomponent magnesium alloys with high tensile strength,ductility,and stiffness,two extruded Mg_(92−5x)Al_(1.5+3x)Zn_(3)Cu_(3.5+x)Ce_(x)(x=0.5 and 1,labeled as C0.5 and C1)alloys were designed.The results reveal that the ultimate tensile strength,yield strength(YS),and fracture strain of the C0.5 alloy are simultaneously improved compared to those of the C1 alloy,with values of 346 MPa,312 MPa,and 11.7%,respectively.This enhancement is primarily attributed to the refinement of numerous secondary phases(micron scale Al_(3)CuCe,micron scale MgZnCu,and nanoscale MgZnCu phases).The calculation of YS shows that the Orowan strengthening and coefficient of thermal expansion mismatch strengthening are the main strengthening mechanisms,and the contribution values of both to the YS are 28 and 70 MPa for C0.5 alloy.In addition,the C0.5 alloy has a greater plasticity than the C1 alloy because the<c+a>slip system is initiated.展开更多
文摘The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-conditioned equations,the activity interaction coeffients between Ce and Al.Si,Ti and Fe alloying elements were determined.The equilibrium constant of the reaction 2[Ce]+3[O]=Ce_(2)O_(3)and the standard free energy of formation of Ce203 in liquid Cu were obtained at 1.200 C.
文摘The thermodynamic properties of Cu-Ce-S and Cu-Y-S liquid solutions were studied by the chemical equilibrium technique at 1200℃. The equilibrium constants and the standard free energies of formation of CeS and YS were determined for the reactions: CeS=[Ce]+[S] and YS = [Y]+[S] . For the solution of Ce_(1) and Y_(l) in pure Cu according to the reactions: Ce_(1)= [Ce] and Y_(1)= [Y] , the standard free energies of solutions were obtained. The first order and second order interaction coefficients between solute elements as well as the activity coefficients γ_(Ce)~0 and γ_Y^0 in liquid Cu were also determined.
基金financially supported by the National Key Research and Development Program of China(No.2022YFB3709300)the Guangdong Major Project of Basic and Applied Basic Research,China(No.2020B0301030006)the Chongqing Special Project of Science and Technology Innovation,China(No.cstc2021yszx-jcyjX0007)。
文摘To obtain lightweight multicomponent magnesium alloys with high tensile strength,ductility,and stiffness,two extruded Mg_(92−5x)Al_(1.5+3x)Zn_(3)Cu_(3.5+x)Ce_(x)(x=0.5 and 1,labeled as C0.5 and C1)alloys were designed.The results reveal that the ultimate tensile strength,yield strength(YS),and fracture strain of the C0.5 alloy are simultaneously improved compared to those of the C1 alloy,with values of 346 MPa,312 MPa,and 11.7%,respectively.This enhancement is primarily attributed to the refinement of numerous secondary phases(micron scale Al_(3)CuCe,micron scale MgZnCu,and nanoscale MgZnCu phases).The calculation of YS shows that the Orowan strengthening and coefficient of thermal expansion mismatch strengthening are the main strengthening mechanisms,and the contribution values of both to the YS are 28 and 70 MPa for C0.5 alloy.In addition,the C0.5 alloy has a greater plasticity than the C1 alloy because the<c+a>slip system is initiated.
