Melt processing is a promising process to fabricate Mg-CNTs(carbon nanotubes)composites with high performance and large dimensions.In this work,the liquidmixing technique and ball-milling processes as well as the stir...Melt processing is a promising process to fabricate Mg-CNTs(carbon nanotubes)composites with high performance and large dimensions.In this work,the liquidmixing technique and ball-milling processes as well as the stirring casting method were used to prepare ZM1-1.0 CNTs-L and ZM1-1.0 CNTs-B composites,respectively.The composites were studied using optical microscopy(OM),Raman spectroscopy,scanning electron microscope(SEM),transmission electron microscope(TEM)and room-temperature tensile test.The results show that the yield strength(YS),ultimate tensile strength(UTS),elongation and microhardness values of the ZM1-1.OCNTs-L composite are improved by 37.3%,29.6%,37.0%and33.3%,respectively,compared with those of ZM1 alloy.The uniform dispersion of CNTs as well as the strong interfacial bonds with the Mg matrix is the main reason for the significant improvement in mechanical properties of the as-cast composite.Liquid mixing combined with the stirring casting method is favorable to fabricate Mg-CNTs composite with high mechanical properties.展开更多
The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical micr...The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical microscopy（OM） and TEM observation.After solution treatment at 420 ℃ for 1 h,three kinds of pre-deformation strains,i.e.0,5% and 10%,were applied to extruded ZM61 bars.Age-hardening curves show that pre-deformation can significantly accelerate the precipitation kinetics and increase peak-hardness value;however,as pre-deformation strain rises from 5% to 10%,there is no gain in peak hardness value.The room temperature（RT） tensile properties demonstrate that increasing the pre-deformation degree can enhance the yield strength（YS） and ultimate tensile strength（UTS） but moderately reduce elongation（EL）;furthermore,the enhancement of YS is larger than that of UTS.No twin can be observed in 5% pre-deformed microstructure;however,a large number of twins are activated after 10% pre-deformation.The peak-aged TEM microstructure shows that pre-deformation can increase the number density of rod-shaped β 1 ＇ precipitates which play a key role in strengthening ZM61 alloy.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51761037)the Scientific Research Foundation of the Education Department of Jiangxi Province(No.GJJ170897)。
文摘Melt processing is a promising process to fabricate Mg-CNTs(carbon nanotubes)composites with high performance and large dimensions.In this work,the liquidmixing technique and ball-milling processes as well as the stirring casting method were used to prepare ZM1-1.0 CNTs-L and ZM1-1.0 CNTs-B composites,respectively.The composites were studied using optical microscopy(OM),Raman spectroscopy,scanning electron microscope(SEM),transmission electron microscope(TEM)and room-temperature tensile test.The results show that the yield strength(YS),ultimate tensile strength(UTS),elongation and microhardness values of the ZM1-1.OCNTs-L composite are improved by 37.3%,29.6%,37.0%and33.3%,respectively,compared with those of ZM1 alloy.The uniform dispersion of CNTs as well as the strong interfacial bonds with the Mg matrix is the main reason for the significant improvement in mechanical properties of the as-cast composite.Liquid mixing combined with the stirring casting method is favorable to fabricate Mg-CNTs composite with high mechanical properties.
基金Project(2007CB613700) supported by the National Basic Research Program of ChinaProject(50725413) supported by the National Natural Science Foundation of China+2 种基金Project(CDJXS11132228) supported by the Fundamental Research Funds for the Central Universities,ChinaProjects(2010DFR50010,2008DFR50040) supported by International Cooperation Program,ChinaProjects (CSTC2009AB4008,2010CSTC-HDLS) supported by Chongqing Sci & Tech Program,China
文摘The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical microscopy（OM） and TEM observation.After solution treatment at 420 ℃ for 1 h,three kinds of pre-deformation strains,i.e.0,5% and 10%,were applied to extruded ZM61 bars.Age-hardening curves show that pre-deformation can significantly accelerate the precipitation kinetics and increase peak-hardness value;however,as pre-deformation strain rises from 5% to 10%,there is no gain in peak hardness value.The room temperature（RT） tensile properties demonstrate that increasing the pre-deformation degree can enhance the yield strength（YS） and ultimate tensile strength（UTS） but moderately reduce elongation（EL）;furthermore,the enhancement of YS is larger than that of UTS.No twin can be observed in 5% pre-deformed microstructure;however,a large number of twins are activated after 10% pre-deformation.The peak-aged TEM microstructure shows that pre-deformation can increase the number density of rod-shaped β 1 ＇ precipitates which play a key role in strengthening ZM61 alloy.
