The microstructures of copper liners of shaped charges prepared byelectroforming technique were investigated by transmission electron microscopy (TEM). Meanwhile, theorientations distributing of the grains in the elec...The microstructures of copper liners of shaped charges prepared byelectroforming technique were investigated by transmission electron microscopy (TEM). Meanwhile, theorientations distributing of the grains in the electroformed copper liners of shaped charges wasexamined by the electron backscattering Kikuchi pattern (EBSP) technique. TEM observations haverevealed that these electroformed copper liners of shaped charges have the grain size of about 1-3mu m and the grains have a preferential orientation distribution along the growth direction. EBSPanalysis has demonstrated that the as-formed copper liners of shaped charges exhibit amicro-texture, i.e. one type of fiber texture, and the preferred growth direction is normal to thesurface of the liners.展开更多
The effect of current density on the morphology of Zn electrodepositsprepared by a flow-channel cell was investigated by scanning electron microscopy (SEM). It was foundthat the morphology of Zn electrodeposits evolve...The effect of current density on the morphology of Zn electrodepositsprepared by a flow-channel cell was investigated by scanning electron microscopy (SEM). It was foundthat the morphology of Zn electrodeposits evolves from thin-layered hexagonal eta -phase crystalsto pyramidal eta -phase particles with increasing the current density. The morphological evolutionat various flow rates was also examined and the results show that the morphological evolution at alower flow rate is more remarkable than that at a higher flow rate with increasing the currentdensity. To reveal the mechanism of the morphological evolution in detail, the atomic configurationon both (0001)_eta and {1100 }_eta planes under different current densities was investigated, it wasnoted that a specify current density could provide a good condition for the layered epitaxialgrowth of hexagonal T)-phase.展开更多
The microstructures in the electroformed copper liners of shapedcharges after high-strain-rate plastic deformation were in-vestigated by transmission electron microscopy(TEM). Meanwhile, theorientation distribution of...The microstructures in the electroformed copper liners of shapedcharges after high-strain-rate plastic deformation were in-vestigated by transmission electron microscopy(TEM). Meanwhile, theorientation distribution of the grains in the recovered slug wasexamined by the electron backscattering Kikuchipattern(EBSP)technique. EBSP analysis illustrated that unlike theas-formed electro- formed copper liners of shaped charges the grainorientations in the recovered slug are distributed along randomly allthe directions after undergoing heavily strain deformation athigh-strain rate. Optical microscopy shows a typicalrecrystallization structure, and TEM exam- ination revealsdislocation cells existed in the thin foil specimen. These resultsindicate that dynamic recovery and recrystallization occur duringthis plastic deformation process, and the associated deformationtemperature is considered to be higher than 0.6 times the meltingpoint of copper.展开更多
基金the National Natural Science Foundation of China (No. 59971008)
文摘The microstructures of copper liners of shaped charges prepared byelectroforming technique were investigated by transmission electron microscopy (TEM). Meanwhile, theorientations distributing of the grains in the electroformed copper liners of shaped charges wasexamined by the electron backscattering Kikuchi pattern (EBSP) technique. TEM observations haverevealed that these electroformed copper liners of shaped charges have the grain size of about 1-3mu m and the grains have a preferential orientation distribution along the growth direction. EBSPanalysis has demonstrated that the as-formed copper liners of shaped charges exhibit amicro-texture, i.e. one type of fiber texture, and the preferred growth direction is normal to thesurface of the liners.
文摘The effect of current density on the morphology of Zn electrodepositsprepared by a flow-channel cell was investigated by scanning electron microscopy (SEM). It was foundthat the morphology of Zn electrodeposits evolves from thin-layered hexagonal eta -phase crystalsto pyramidal eta -phase particles with increasing the current density. The morphological evolutionat various flow rates was also examined and the results show that the morphological evolution at alower flow rate is more remarkable than that at a higher flow rate with increasing the currentdensity. To reveal the mechanism of the morphological evolution in detail, the atomic configurationon both (0001)_eta and {1100 }_eta planes under different current densities was investigated, it wasnoted that a specify current density could provide a good condition for the layered epitaxialgrowth of hexagonal T)-phase.
基金financially supported by the National Natural Science Foundation of China (No.59971008).
文摘The microstructures in the electroformed copper liners of shapedcharges after high-strain-rate plastic deformation were in-vestigated by transmission electron microscopy(TEM). Meanwhile, theorientation distribution of the grains in the recovered slug wasexamined by the electron backscattering Kikuchipattern(EBSP)technique. EBSP analysis illustrated that unlike theas-formed electro- formed copper liners of shaped charges the grainorientations in the recovered slug are distributed along randomly allthe directions after undergoing heavily strain deformation athigh-strain rate. Optical microscopy shows a typicalrecrystallization structure, and TEM exam- ination revealsdislocation cells existed in the thin foil specimen. These resultsindicate that dynamic recovery and recrystallization occur duringthis plastic deformation process, and the associated deformationtemperature is considered to be higher than 0.6 times the meltingpoint of copper.
