A two-dimensional coupled thermo-mechanical model is used to simulate the progress of milling mild carbon steel with continuous chip formation. Deformation of the workpiece is treated as elastic-plastic with isotropic...A two-dimensional coupled thermo-mechanical model is used to simulate the progress of milling mild carbon steel with continuous chip formation. Deformation of the workpiece is treated as elastic-plastic with isotropic strain-hardening. An analysis of the properties of temperature-dependent materials is employed. The chip separation is achieved by the adaptive remeshing strategy module found in commercial finite element code Marc. In order to increase the computational efficiency and accuracy, we implement a customized subroutine into the Marc code to define local refinement at the tool tip. Measurements are taken of the shape of the chip, the temperature, stress, strain and strain-rate fields. The values of the cutting forces obtained from the simulations agree well with those obtained from the cutting experiments.展开更多
Several transition metal oxides,including α-Fe2O3,Fe3O4,Co3O4,NiO,CuO and ZnO,were synthesized via an easily controlled hydrothermal method at assistance of organic amine(cyclohexylamine or triethylamine).The synthes...Several transition metal oxides,including α-Fe2O3,Fe3O4,Co3O4,NiO,CuO and ZnO,were synthesized via an easily controlled hydrothermal method at assistance of organic amine(cyclohexylamine or triethylamine).The synthesized samples were identified and characterized by X-ray diffraction(XRD),Transmission Electron Microscopy(TEM),High-resolution Electron Microscopy(HR-TEM),Field Emission Scanning Electron Microscopy(FE-SEM),N2 adsorption/desorption measurement.The resultant metal oxides displayed various morphologies in shape.The as-prepared samples were used as electrocatalysts(CuO was excluded) modified on a glassy carbon electrode for p-nitrophenol reduction in a basic solution.Fe3O4 and Co3O4 samples showed higher catalytic activities.展开更多
文摘A two-dimensional coupled thermo-mechanical model is used to simulate the progress of milling mild carbon steel with continuous chip formation. Deformation of the workpiece is treated as elastic-plastic with isotropic strain-hardening. An analysis of the properties of temperature-dependent materials is employed. The chip separation is achieved by the adaptive remeshing strategy module found in commercial finite element code Marc. In order to increase the computational efficiency and accuracy, we implement a customized subroutine into the Marc code to define local refinement at the tool tip. Measurements are taken of the shape of the chip, the temperature, stress, strain and strain-rate fields. The values of the cutting forces obtained from the simulations agree well with those obtained from the cutting experiments.
基金supported by the Excellent Young Academic Foundation of Anhui Province (2010SQRL163)
文摘Several transition metal oxides,including α-Fe2O3,Fe3O4,Co3O4,NiO,CuO and ZnO,were synthesized via an easily controlled hydrothermal method at assistance of organic amine(cyclohexylamine or triethylamine).The synthesized samples were identified and characterized by X-ray diffraction(XRD),Transmission Electron Microscopy(TEM),High-resolution Electron Microscopy(HR-TEM),Field Emission Scanning Electron Microscopy(FE-SEM),N2 adsorption/desorption measurement.The resultant metal oxides displayed various morphologies in shape.The as-prepared samples were used as electrocatalysts(CuO was excluded) modified on a glassy carbon electrode for p-nitrophenol reduction in a basic solution.Fe3O4 and Co3O4 samples showed higher catalytic activities.
