In order to obtain good strength−plasticity synergy for a medium entropy alloy(MEA)CrCoNi,cold rolling,asymmetric rolling,cryorolling and asymmetric-cryorolling with subsequent annealing at different temperatures were...In order to obtain good strength−plasticity synergy for a medium entropy alloy(MEA)CrCoNi,cold rolling,asymmetric rolling,cryorolling and asymmetric-cryorolling with subsequent annealing at different temperatures were conducted.The results showed that the asymmetric-cryorolled alloy achieved a high strength of over 1.6 GPa.After annealing at 1073 K,it retained a high strength of~1 GPa while the elongation reached nearly 60%.After annealing,the heterogeneous characteristics were formed in asymmetric-cryorolled samples,which were found to be more distinct than those of the samples subjected to asymmetric rolling.This resulted in the generation of high strength and ductility.展开更多
The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium...The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement.展开更多
Based on the maximum fuzzy entropy principle,the edge image with low contrast is optimally classified into two classes adaptively,under the condition of probability partition and fuzzy partition.The optimal threshold ...Based on the maximum fuzzy entropy principle,the edge image with low contrast is optimally classified into two classes adaptively,under the condition of probability partition and fuzzy partition.The optimal threshold is used as the classified threshold value,and a local parametric gray-level transformation is applied to the obtained classes.By means of two parameters representing,the homogeneity of the regions in edge image is improved.The excellent performance of the proposed technique is exercisable through simulation results on a set of test images.It is shown how the extracted and enhanced edges provide an efficient edge-representation of images.It is shown that the proposed technique possesses excellent performance in homogeneity through simulations on a set of test images,and the extracted and enhanced edges provide an efficient edge-representation of images.展开更多
For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator m...For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 Since A #0,r B = A and A #l,r B = B, weregard A#t,rB as apath combining A and B.Our aim is to show the essential properties of St,r （AIB）. The Tsallis relative operator entropy by Yanagi, Kuriyama and Furuichi can also be expanded, and by using this, we can give an expanded operator valued a-divergence and obtain its properties.展开更多
A light-weight high-entropy alloy （LWHEA） A120Be20Fe10SilsTi35 has been developed to have unique mechanical properties and oxidation resistance. One major and two minor phases are observed in the as-east microstruct...A light-weight high-entropy alloy （LWHEA） A120Be20Fe10SilsTi35 has been developed to have unique mechanical properties and oxidation resistance. One major and two minor phases are observed in the as-east microstructure. The density of the alloy is 3.91 gcm-3, and its hardness is HV 911, which is higher than quartz. The hardness and hardness to density ratio are the highest of all light-weight alloys reported before. In addition, it has excellent oxidation resistance at 700℃ and 900℃, which far exceeds that of Ti-6A1-4V. Thus, the combination of properties is promising for high-temperature applications, which require light weight, wear-resistant and oxidation-resistant components.展开更多
Fatigue failures cost approximately 4% of the United States' gross domestic product(GDP). The design of highly fatigue-resistant materials is always in demand. Different from conventional strategies of alloy desig...Fatigue failures cost approximately 4% of the United States' gross domestic product(GDP). The design of highly fatigue-resistant materials is always in demand. Different from conventional strategies of alloy design, high-entropy alloys(HEAs) are defined as materials with five or more principal elements, which could be solid solutions. This locally-disordered structure is expected to lead to unique fatigue-resistant properties. In this review, the studies of the fatigue behavior of HEAs during the last five years are summarized. The four-point-bending high-cycle fatigue coupled with statistical modelling, and the fatigue-crack-growth behavior of HEAs, are reviewed. The effects of sample defects and nanotwins-deformation mechanisms on four-point-bending high-cycle fatigue of HEAs are discussed in detail. The influence of stress ratio and temperature on fatigue-crack-growth characteristics of HEAs is also discussed. HEAs could exhibit comparable or greater fatigue properties, relative to conventional materials. Finally,the possible future work regarding the fatigue behavior of HEAs is suggested.展开更多
In this manuscript, the FeCrCoNi high entropy alloy strengthened by nano-Y203 particles was synthesized via mechanical alloying and spark plasma sintering. Effects of Y203 additions on the microstructure and mechanica...In this manuscript, the FeCrCoNi high entropy alloy strengthened by nano-Y203 particles was synthesized via mechanical alloying and spark plasma sintering. Effects of Y203 additions on the microstructure and mechanical properties were investigated. The oxide-dispersion-strengthened （ODS） high-entropy alloy bearing 5wt% Y203 was found to have a finer grain with respect to the single-phase face-centered cubic （FCC） alloy without oxides. Consequently, the yield strength increased from 654 to 1754 MPa, and the fracture strength reached up to 2325 MPa while the plasticity decreased appreciably for the ODS high-entropy alloy. The synergic effects of grain size hardening and particle strengthening on mechanical properties of the ODS HEA were discussed. This finding indicates that the addition of nano-scaled oxides is an effective and feasible approach to designing HEAs with superior mechanical properties.展开更多
This paper considers the problem of estimating the finite population total in two-phase sampling when some information on auxiliary variable is available. The authors employ an informationtheoretic approach which make...This paper considers the problem of estimating the finite population total in two-phase sampling when some information on auxiliary variable is available. The authors employ an informationtheoretic approach which makes use of effective distance between the estimated probabilities and the empirical frequencies. It is shown that the proposed cross-entropy minimization estimator is more efficient than the usual estimator and has some desirable large sample properties. With some necessary modifications, the method can be applied to two-phase sampling for stratification and non-response. A simulation study is presented to assess the finite sample performance of the proposed estimator.展开更多
This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential...This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential. The analysis of the quantum mechanical probability has been obtained via the Fisher information. The variance information of this potential is equally computed. This controls both the chemical properties and physical properties of some of the molecular systems. We have observed the behaviour of the Shannon entropy. Renyi entropy, Fisher information and variance with the quantum number n respectively.展开更多
基金supported by the Hunan High-Tech Industry Science and Technology Innovation Leading Plan,China(No.2020GK2032)the Huxiang High-Level Talent Gathering Project of Hunan Province,China(No.2018RS3015)+1 种基金the Innovation Driven Program of Central South University,China(No.2019CX006)the Research Fund of the Key Laboratory of High Performance Complex Manufacturing at Central South University,China。
文摘In order to obtain good strength−plasticity synergy for a medium entropy alloy(MEA)CrCoNi,cold rolling,asymmetric rolling,cryorolling and asymmetric-cryorolling with subsequent annealing at different temperatures were conducted.The results showed that the asymmetric-cryorolled alloy achieved a high strength of over 1.6 GPa.After annealing at 1073 K,it retained a high strength of~1 GPa while the elongation reached nearly 60%.After annealing,the heterogeneous characteristics were formed in asymmetric-cryorolled samples,which were found to be more distinct than those of the samples subjected to asymmetric rolling.This resulted in the generation of high strength and ductility.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10674038, 10604042National Basic Research Program of China under Grant No. 2006CB302901
文摘The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement.
文摘Based on the maximum fuzzy entropy principle,the edge image with low contrast is optimally classified into two classes adaptively,under the condition of probability partition and fuzzy partition.The optimal threshold is used as the classified threshold value,and a local parametric gray-level transformation is applied to the obtained classes.By means of two parameters representing,the homogeneity of the regions in edge image is improved.The excellent performance of the proposed technique is exercisable through simulation results on a set of test images.It is shown how the extracted and enhanced edges provide an efficient edge-representation of images.It is shown that the proposed technique possesses excellent performance in homogeneity through simulations on a set of test images,and the extracted and enhanced edges provide an efficient edge-representation of images.
文摘For strictly positive operators A and B, and for x ∈ [0,1] and r ∈[-1,1], we investigate the operator power mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 If r = O, this is reduced to the geometric operator mean A#x,rB=A1/2{（1-x）/＋x（a-1＊2BA-1/2）r}1/rA1/2 Since A #0,r B = A and A #l,r B = B, weregard A#t,rB as apath combining A and B.Our aim is to show the essential properties of St,r （AIB）. The Tsallis relative operator entropy by Yanagi, Kuriyama and Furuichi can also be expanded, and by using this, we can give an expanded operator valued a-divergence and obtain its properties.
文摘A light-weight high-entropy alloy （LWHEA） A120Be20Fe10SilsTi35 has been developed to have unique mechanical properties and oxidation resistance. One major and two minor phases are observed in the as-east microstructure. The density of the alloy is 3.91 gcm-3, and its hardness is HV 911, which is higher than quartz. The hardness and hardness to density ratio are the highest of all light-weight alloys reported before. In addition, it has excellent oxidation resistance at 700℃ and 900℃, which far exceeds that of Ti-6A1-4V. Thus, the combination of properties is promising for high-temperature applications, which require light weight, wear-resistant and oxidation-resistant components.
基金supported by the Department of Energy(DOE),Office of Fossil Energy,National Energy Technology Laboratory(Grant No.DE-FE-0024054,DE-FE-0011194)the U.S.Army Research Office Project(Grant No.W911NF-13-1-0438)+4 种基金the National Science Foundation(DMR-1611180)the QuesTek Innovation LLC(limited liability company)the Ministry of Science and Technology of Taiwan(Grant No.MOST105-2221-E-007-017-MY3)the Department of Materials Science and Engineering at the National Tsing Hua University(Taiwan)the School of Materials Science and Engineering of the Dalian University of Technology,China
文摘Fatigue failures cost approximately 4% of the United States' gross domestic product(GDP). The design of highly fatigue-resistant materials is always in demand. Different from conventional strategies of alloy design, high-entropy alloys(HEAs) are defined as materials with five or more principal elements, which could be solid solutions. This locally-disordered structure is expected to lead to unique fatigue-resistant properties. In this review, the studies of the fatigue behavior of HEAs during the last five years are summarized. The four-point-bending high-cycle fatigue coupled with statistical modelling, and the fatigue-crack-growth behavior of HEAs, are reviewed. The effects of sample defects and nanotwins-deformation mechanisms on four-point-bending high-cycle fatigue of HEAs are discussed in detail. The influence of stress ratio and temperature on fatigue-crack-growth characteristics of HEAs is also discussed. HEAs could exhibit comparable or greater fatigue properties, relative to conventional materials. Finally,the possible future work regarding the fatigue behavior of HEAs is suggested.
基金supported by the National Natural Science Foundation of China(Grant Nos.51671018,51671021&51531001)Higher Education Discipline Innovation Project(Grant No.B07003)+2 种基金International S&T Cooperation Program of China(Grant No.2015DFG52600)the Program for Changjiang Scholars and Innovative Research Team in University of China(Grant No.IRT_14R05)the Projects of SKL-AMM-USTB(Grant Nos.2016Z-04,2016-09&2016Z-16)
文摘In this manuscript, the FeCrCoNi high entropy alloy strengthened by nano-Y203 particles was synthesized via mechanical alloying and spark plasma sintering. Effects of Y203 additions on the microstructure and mechanical properties were investigated. The oxide-dispersion-strengthened （ODS） high-entropy alloy bearing 5wt% Y203 was found to have a finer grain with respect to the single-phase face-centered cubic （FCC） alloy without oxides. Consequently, the yield strength increased from 654 to 1754 MPa, and the fracture strength reached up to 2325 MPa while the plasticity decreased appreciably for the ODS high-entropy alloy. The synergic effects of grain size hardening and particle strengthening on mechanical properties of the ODS HEA were discussed. This finding indicates that the addition of nano-scaled oxides is an effective and feasible approach to designing HEAs with superior mechanical properties.
基金supported by the National Natural Science Foundation of China under Grant No.61070236
文摘This paper considers the problem of estimating the finite population total in two-phase sampling when some information on auxiliary variable is available. The authors employ an informationtheoretic approach which makes use of effective distance between the estimated probabilities and the empirical frequencies. It is shown that the proposed cross-entropy minimization estimator is more efficient than the usual estimator and has some desirable large sample properties. With some necessary modifications, the method can be applied to two-phase sampling for stratification and non-response. A simulation study is presented to assess the finite sample performance of the proposed estimator.
文摘This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential. The analysis of the quantum mechanical probability has been obtained via the Fisher information. The variance information of this potential is equally computed. This controls both the chemical properties and physical properties of some of the molecular systems. We have observed the behaviour of the Shannon entropy. Renyi entropy, Fisher information and variance with the quantum number n respectively.
