The magnetic properties, structure defects of electrodeposited Fe-Ni-P alloys with various compositions and the thermostability at amorphous state have been studied by DSC, positron annihilation and electronic integra...The magnetic properties, structure defects of electrodeposited Fe-Ni-P alloys with various compositions and the thermostability at amorphous state have been studied by DSC, positron annihilation and electronic integrating instrument methods. The results show that the thermostability of amorphous Fe-Ni-P alloys increases with Fe content. Emergence and recrystallization of stable phases defer as the P content of the coating increases. The minimum Hc, Br and Ph occur at 9.4 P (wt pct) content. Maximum Hc, Br and Ph occur at the weight ratio of Fe to Ni equaling to 1/9.展开更多
Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the li...Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental展开更多
1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subs...1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave,展开更多
The strengthening effect of a Zn alloy reinforced by SiC particulate was examined. Based on the results of SEM in-situ fracture observation and stress field analysis by finite element method, it is believed that the r...The strengthening effect of a Zn alloy reinforced by SiC particulate was examined. Based on the results of SEM in-situ fracture observation and stress field analysis by finite element method, it is believed that the reinforcing effect of this composite is due to the combination of strain and stress hardening in the matrix.展开更多
In this paper, moisture absorption characteristics of Carbon/Glass and Carbon/Aramid hybrid composites with bo types of matrices are investigated. The weight gain of the specimens are tested at 80℃. It is found that ...In this paper, moisture absorption characteristics of Carbon/Glass and Carbon/Aramid hybrid composites with bo types of matrices are investigated. The weight gain of the specimens are tested at 80℃. It is found that the water diffusion in hybrid composites can be described by Fickian process. The Step-by-step model and new thermal model are developed to estimate the equilibrium moisture content (Mm) and water diffusion coefficient (D) in hybrid composites using the hybrid structure parameters (hybrid ratio and hybrid intedece number). The estimated values are in good agreement with the experimental results.展开更多
The effects of positron diffusion on the measured S parameter have been investigated by a point- source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the ...The effects of positron diffusion on the measured S parameter have been investigated by a point- source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.展开更多
Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.M...Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.Methods Two hundred and展开更多
Ⅲ-ⅤSemiconductors containing a small amount of Bi,known as dilute bismides,have attracted great interest in recent years,due to the large band-gap reduction and other unique properties[1,2].Previous studies have bee...Ⅲ-ⅤSemiconductors containing a small amount of Bi,known as dilute bismides,have attracted great interest in recent years,due to the large band-gap reduction and other unique properties[1,2].Previous studies have been primarily focused on the growth and optical properties of the GaAs-based bismuthides[3],while the properties of other dilute bismides are less well understood.Berding et al.[4]theoretically predicted that InPBi is expected to be展开更多
Understanding composition effects is crucial for alloy design and development. To date, there is a lack of research comprehensively addressing the effect of alloy composition on dynamic precipitation, segregation and ...Understanding composition effects is crucial for alloy design and development. To date, there is a lack of research comprehensively addressing the effect of alloy composition on dynamic precipitation, segregation and grain refinement under severe-plastic-deformation processing. This research investigates Al-x Si alloys with x = 0.1, 0.5 and 1.0 at.% Si processed by high pressure torsion(HPT) at room temperature by using transmission electron microscopy, transmission Kikuchi diffraction and atom probe tomography. The alloys exhibit interesting composition-dependent grain refinement and fast dynamic decomposition under HPT processing. Si atoms segregate at dislocations and Si precipitates form at grain boundaries(GBs) depending on the Si content of the alloys. The growth of Si precipitates consumes most Si atoms segregating at GBs, hence the size and distribution of the Si precipitates become predominant factors in controlling the grain size of the decomposed Al-Si alloys after HPT processing. The hardness of the Al-Si alloys is well correlated with a combination of grain-refinement strengthening and the decomposition-induced softening.展开更多
One-dimensional artificial scattering planes can form in the direction perpendicular to the surface of the films when the compositional modulation period is shorter. Similar to real crystal lattice planes, these artif...One-dimensional artificial scattering planes can form in the direction perpendicular to the surface of the films when the compositional modulation period is shorter. Similar to real crystal lattice planes, these artificial scattering planes produce Bragg diffraction with X-ray radiation. Since the modulation period is longer than the general lattice period, the Bragg diffraction peak appears at the position of lower angle (2θ is generally lower than 10°). The diffraction peaks produced by compositional modulation are called modulation peaks.展开更多
Magnetoelectric(ME)composites have recently attracted an ever-increasing interest and provoked a great number of research activities,driven by the potential applications in novel multifunctional devices,such as sensor...Magnetoelectric(ME)composites have recently attracted an ever-increasing interest and provoked a great number of research activities,driven by the potential applications in novel multifunctional devices,such as sensors and transducers[1].Direct ME effect,which describe the appearance of an electric polarization P upon applying a magnetic field H,is usually evaluated by the展开更多
In the current work,a parallel comparison of the influence of Al,Mo and Ti,on the microstructure and strengthening of the CoCrFeNi alloy was conducted.To achieve this,inconsistencies on variables including the extent ...In the current work,a parallel comparison of the influence of Al,Mo and Ti,on the microstructure and strengthening of the CoCrFeNi alloy was conducted.To achieve this,inconsistencies on variables including the extent of alloying,thermomechanical processing and property-evaluation method were avoided.Microstructurally,following cold-rolling,annealing of the 4 at.%Al-doped alloys at 800-1000℃ did not result in phase separation;nevertheless,that of the 4 at.%Mo-and Ti-doped alloys led to the respective formation ofσandηphase and,consequently,caused extra strengthening through the Orowan dislocation bypassing mechanism.Our systematic qualitative analysis and DFT calculations showed that Al and Ti are more effective than Mo in reducing the stacking fault energy(SFE)of the CoCrFeNi alloy,because they can induce more considerable deformation of electronic density,making the gliding of atomic layers easier.Following identical thermomechnical processing,Al-,Mo-,and Ti-doping causes different extent of solid solution strengthening and grain boundary strengthening.Mo causes the most pronounced solid solution strengthening but does not benefit the grain boundary strengthening;in contrast,the effectiveness of grain boundary strengthening is boosted by the doping Al and Ti.Current analyses support that Labusch instead of Fleischer mechanism is applicable to explain the differences in solid solution strengthening,and the observed differences in grain boundary strengthening arise from the different tendency of Al,Mo and Ti to reduce the SFE of CoCrFeNi.In addition,we determined the value of the dimensionless parameter f in the Labusch model for CoCrFeNi-based alloys and observed a close relation between Hall-Petch slope and SFE.Although more in-depth studies are needed to provide full and mechanistic understandings,both these findings in fact presents significant values toward designing novel singlephase high-strength CoCrFeNi-based alloys through manipulating the solid solution and grain boundary strengthening by compositional tuning.展开更多
文摘The magnetic properties, structure defects of electrodeposited Fe-Ni-P alloys with various compositions and the thermostability at amorphous state have been studied by DSC, positron annihilation and electronic integrating instrument methods. The results show that the thermostability of amorphous Fe-Ni-P alloys increases with Fe content. Emergence and recrystallization of stable phases defer as the P content of the coating increases. The minimum Hc, Br and Ph occur at 9.4 P (wt pct) content. Maximum Hc, Br and Ph occur at the weight ratio of Fe to Ni equaling to 1/9.
文摘Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental
文摘1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave,
基金This project is supported by the National Natural Science Foundation of China(No.59971017).
文摘The strengthening effect of a Zn alloy reinforced by SiC particulate was examined. Based on the results of SEM in-situ fracture observation and stress field analysis by finite element method, it is believed that the reinforcing effect of this composite is due to the combination of strain and stress hardening in the matrix.
文摘In this paper, moisture absorption characteristics of Carbon/Glass and Carbon/Aramid hybrid composites with bo types of matrices are investigated. The weight gain of the specimens are tested at 80℃. It is found that the water diffusion in hybrid composites can be described by Fickian process. The Step-by-step model and new thermal model are developed to estimate the equilibrium moisture content (Mm) and water diffusion coefficient (D) in hybrid composites using the hybrid structure parameters (hybrid ratio and hybrid intedece number). The estimated values are in good agreement with the experimental results.
文摘The effects of positron diffusion on the measured S parameter have been investigated by a point- source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.
文摘Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.Methods Two hundred and
基金supported by the National Basic Research Program of China(Grant No.2014CB643900)the National Natural Science Foundation of China(Grant Nos.61225021,11474272,11204296,and 11474247)
文摘Ⅲ-ⅤSemiconductors containing a small amount of Bi,known as dilute bismides,have attracted great interest in recent years,due to the large band-gap reduction and other unique properties[1,2].Previous studies have been primarily focused on the growth and optical properties of the GaAs-based bismuthides[3],while the properties of other dilute bismides are less well understood.Berding et al.[4]theoretically predicted that InPBi is expected to be
基金funded by the financial support of the National Natural Science Foundation of China (No.51751120 and No.51604156)support and the assistance of Material Characterization and Research Center of Nanjing University of Science and Technology。
文摘Understanding composition effects is crucial for alloy design and development. To date, there is a lack of research comprehensively addressing the effect of alloy composition on dynamic precipitation, segregation and grain refinement under severe-plastic-deformation processing. This research investigates Al-x Si alloys with x = 0.1, 0.5 and 1.0 at.% Si processed by high pressure torsion(HPT) at room temperature by using transmission electron microscopy, transmission Kikuchi diffraction and atom probe tomography. The alloys exhibit interesting composition-dependent grain refinement and fast dynamic decomposition under HPT processing. Si atoms segregate at dislocations and Si precipitates form at grain boundaries(GBs) depending on the Si content of the alloys. The growth of Si precipitates consumes most Si atoms segregating at GBs, hence the size and distribution of the Si precipitates become predominant factors in controlling the grain size of the decomposed Al-Si alloys after HPT processing. The hardness of the Al-Si alloys is well correlated with a combination of grain-refinement strengthening and the decomposition-induced softening.
文摘One-dimensional artificial scattering planes can form in the direction perpendicular to the surface of the films when the compositional modulation period is shorter. Similar to real crystal lattice planes, these artificial scattering planes produce Bragg diffraction with X-ray radiation. Since the modulation period is longer than the general lattice period, the Bragg diffraction peak appears at the position of lower angle (2θ is generally lower than 10°). The diffraction peaks produced by compositional modulation are called modulation peaks.
基金supported by the National Natural Science Foundation of China (51402164)
文摘Magnetoelectric(ME)composites have recently attracted an ever-increasing interest and provoked a great number of research activities,driven by the potential applications in novel multifunctional devices,such as sensors and transducers[1].Direct ME effect,which describe the appearance of an electric polarization P upon applying a magnetic field H,is usually evaluated by the
基金financially supported by the National Natural Science Foundation of China(No.51901077)the Science and Technology Innovation Platform and Talent Plan of Hunan Province(No.2019RS1020)+1 种基金the open project of State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body(No.71865003)Hunan University,Changsha,China.YG acknowledges support from NSF DMR 1809640。
文摘In the current work,a parallel comparison of the influence of Al,Mo and Ti,on the microstructure and strengthening of the CoCrFeNi alloy was conducted.To achieve this,inconsistencies on variables including the extent of alloying,thermomechanical processing and property-evaluation method were avoided.Microstructurally,following cold-rolling,annealing of the 4 at.%Al-doped alloys at 800-1000℃ did not result in phase separation;nevertheless,that of the 4 at.%Mo-and Ti-doped alloys led to the respective formation ofσandηphase and,consequently,caused extra strengthening through the Orowan dislocation bypassing mechanism.Our systematic qualitative analysis and DFT calculations showed that Al and Ti are more effective than Mo in reducing the stacking fault energy(SFE)of the CoCrFeNi alloy,because they can induce more considerable deformation of electronic density,making the gliding of atomic layers easier.Following identical thermomechnical processing,Al-,Mo-,and Ti-doping causes different extent of solid solution strengthening and grain boundary strengthening.Mo causes the most pronounced solid solution strengthening but does not benefit the grain boundary strengthening;in contrast,the effectiveness of grain boundary strengthening is boosted by the doping Al and Ti.Current analyses support that Labusch instead of Fleischer mechanism is applicable to explain the differences in solid solution strengthening,and the observed differences in grain boundary strengthening arise from the different tendency of Al,Mo and Ti to reduce the SFE of CoCrFeNi.In addition,we determined the value of the dimensionless parameter f in the Labusch model for CoCrFeNi-based alloys and observed a close relation between Hall-Petch slope and SFE.Although more in-depth studies are needed to provide full and mechanistic understandings,both these findings in fact presents significant values toward designing novel singlephase high-strength CoCrFeNi-based alloys through manipulating the solid solution and grain boundary strengthening by compositional tuning.
