The interfacial adhesive properties ofpolypropylene/stainless steel were studied by the blister test. The polypropylene film with a squared free-standing window was pressured by oil from one side of film. The correspo...The interfacial adhesive properties ofpolypropylene/stainless steel were studied by the blister test. The polypropylene film with a squared free-standing window was pressured by oil from one side of film. The corresponding deformation field was observed by a digital speckle correlation method. The experimental results show that the squared film deforms and debonds from stainless steel with the increase of pressure. The debonding of the squared film in initiates from the center of edge and extends to the comer, and then the deformation of film evolves from square to circle shape. The interfacial adhesive energy of polypropylene/stainless steel is (22.60±1.55) J/m2, which is in agreement with that measured by film with a circular window.展开更多
A mesoscale modeling methodology is proposed to predict the strain induced abnormal grain growth in the annealing process of deformed aluminum alloys. Firstly, crystal plasticity finite element(CPFE) analysis is perfo...A mesoscale modeling methodology is proposed to predict the strain induced abnormal grain growth in the annealing process of deformed aluminum alloys. Firstly, crystal plasticity finite element(CPFE) analysis is performed to calculate dislocation density and stored deformation energy distribution during the plastic deformation. A modified phase field(PF) model is then established by extending the continuum field method to consider both stored energy and local interface curvature as driving forces of grain boundary migration. An interpolation mapping approach is adopted to transfer the stored energy distribution from CPFE to PF efficiently. This modified PF model is implemented to a hypothetical bicrystal firstly for verification and then the coupled CPFE-PF framework is further applied to simulating the 2D synthetic polycrystalline microstructure evolution in annealing process of deformed AA3102 aluminum alloy.Results show that the nuclei with low stored energy embedded within deformed matrix tend to grow up, and abnormal large grains occur when the deformation is close to the critical plastic strain, attributing to the limited number of recrystallized nuclei and inhomogeneity of the stored energy.展开更多
The authors offered the new formula of the thermodynamic functions in a magnetic field. The authors have also found that thermodynamic functions of internal energy dUand free energy dF changes in the magnetic field.
Reciprocating friction characteristics of magneto-rheological (MR) fluid for aluminum under a magnetic field at different loads and oscillation frequencies were studied when MR fluids were worked in reciprocating mo...Reciprocating friction characteristics of magneto-rheological (MR) fluid for aluminum under a magnetic field at different loads and oscillation frequencies were studied when MR fluids were worked in reciprocating motions such as in dampers for automobiles, and surface polishing and other finishing. Thus, experiments were carried out to evaluate the reciprocating friction characteristic of MR fluid for aluminum. The obtained data from the tests are sorted in groups depending on various loads and oscillation frequencies, to analyze the relationship between test condition and travel cycle. Surfaces of specimens were compared by measuring the surface roughness and observing the surface images. The performance of reciprocating friction characteristics of MR fluid for aluminum is evaluated through analyzing the experiment results.展开更多
The ability to control magnetic vortex is critical for their potential applications in spintronic devices.Traditional methods including magnetic field,spin-polarized current etc.have been used to flip the core and/or ...The ability to control magnetic vortex is critical for their potential applications in spintronic devices.Traditional methods including magnetic field,spin-polarized current etc.have been used to flip the core and/or reverse circulation of vortex.However,it is challenging for deterministic electric-field control of the single magnetic vortex textures with time-reversal broken symmetry and no planar magnetic anisotropy.Here it is reported that a deterministic reversal of single magnetic vortex circulation can be driven back and forth by a space-varying strain in multiferroic heterostructures,which is controlled by using a bi-axial pulsed electric field.Phase-field simulation reveals the mechanism of the emerging magnetoelastic energy with the space variation and visualizes the reversal pathway of the vortex.This deterministic electric-field control of the single magnetic vortex textures demonstrates a new approach to integrate the low-dimensional spin texture into the magnetoelectric thin film devices with low energy consumption.展开更多
基金Projects(11102176,11172258,10828205)supported by the National Natural Science Foundation of China
文摘The interfacial adhesive properties ofpolypropylene/stainless steel were studied by the blister test. The polypropylene film with a squared free-standing window was pressured by oil from one side of film. The corresponding deformation field was observed by a digital speckle correlation method. The experimental results show that the squared film deforms and debonds from stainless steel with the increase of pressure. The debonding of the squared film in initiates from the center of edge and extends to the comer, and then the deformation of film evolves from square to circle shape. The interfacial adhesive energy of polypropylene/stainless steel is (22.60±1.55) J/m2, which is in agreement with that measured by film with a circular window.
基金the financial support from the National Natural Science Foundation of China (Nos. U2141215, 52105384 and 52075325)the support of Materials Genome Initiative Center, Shanghai Jiao Tong University, China。
文摘A mesoscale modeling methodology is proposed to predict the strain induced abnormal grain growth in the annealing process of deformed aluminum alloys. Firstly, crystal plasticity finite element(CPFE) analysis is performed to calculate dislocation density and stored deformation energy distribution during the plastic deformation. A modified phase field(PF) model is then established by extending the continuum field method to consider both stored energy and local interface curvature as driving forces of grain boundary migration. An interpolation mapping approach is adopted to transfer the stored energy distribution from CPFE to PF efficiently. This modified PF model is implemented to a hypothetical bicrystal firstly for verification and then the coupled CPFE-PF framework is further applied to simulating the 2D synthetic polycrystalline microstructure evolution in annealing process of deformed AA3102 aluminum alloy.Results show that the nuclei with low stored energy embedded within deformed matrix tend to grow up, and abnormal large grains occur when the deformation is close to the critical plastic strain, attributing to the limited number of recrystallized nuclei and inhomogeneity of the stored energy.
文摘The authors offered the new formula of the thermodynamic functions in a magnetic field. The authors have also found that thermodynamic functions of internal energy dUand free energy dF changes in the magnetic field.
基金supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF)funded by the Ministry of Education, Science and Technology of the government of Korea (Grant No. 2010-0025763)+1 种基金supported by the MSIP (Ministry of Science, ICT&Future Planning), Korea, under the C-ITRC (Convergence Information Technology Research Center) support program (NIPA-2013-H0401-13-1006) supervised by the NIPA(National IT Industry Promotion Agency)supported by INHA University
文摘Reciprocating friction characteristics of magneto-rheological (MR) fluid for aluminum under a magnetic field at different loads and oscillation frequencies were studied when MR fluids were worked in reciprocating motions such as in dampers for automobiles, and surface polishing and other finishing. Thus, experiments were carried out to evaluate the reciprocating friction characteristic of MR fluid for aluminum. The obtained data from the tests are sorted in groups depending on various loads and oscillation frequencies, to analyze the relationship between test condition and travel cycle. Surfaces of specimens were compared by measuring the surface roughness and observing the surface images. The performance of reciprocating friction characteristics of MR fluid for aluminum is evaluated through analyzing the experiment results.
基金supported by the National Key Research and Development Program of China(2016YFA0302300 and 2017YFA0206200)Basic Science Center Program of the National Natural Science Foundation of China(51788104)+5 种基金National Natural Science Foundation of China(11974052,51972028)Beijing Natural Science Foundation(Z190008)Chinese Academy of Sciences Interdisciplinary Innovation Teamfunded by the Director,Office of Science,Office of Basic Energy Sciences,Materials Science and Engineering Department of the US Department of Energy(DOE)in the Quantum Materials Program(KC2202)under Contract No.DEAC02-05CH11231the support by the Science Alliance Joint Directed Research&Development Programthe Transdisciplinary Academy Program at the University of Tennessee。
文摘The ability to control magnetic vortex is critical for their potential applications in spintronic devices.Traditional methods including magnetic field,spin-polarized current etc.have been used to flip the core and/or reverse circulation of vortex.However,it is challenging for deterministic electric-field control of the single magnetic vortex textures with time-reversal broken symmetry and no planar magnetic anisotropy.Here it is reported that a deterministic reversal of single magnetic vortex circulation can be driven back and forth by a space-varying strain in multiferroic heterostructures,which is controlled by using a bi-axial pulsed electric field.Phase-field simulation reveals the mechanism of the emerging magnetoelastic energy with the space variation and visualizes the reversal pathway of the vortex.This deterministic electric-field control of the single magnetic vortex textures demonstrates a new approach to integrate the low-dimensional spin texture into the magnetoelectric thin film devices with low energy consumption.