Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities o...Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching would reduce with the increase of Zn content and the precipitation of η-Zn phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD. The microstructure change during aging was observed by TEM.展开更多
The interaction of spinodal decomposition and recrystallization process, and the characteristic of recrystallization in Cu-Ni-Fe alloy aged at different temperatures after solution-treatment and cold rolling have been...The interaction of spinodal decomposition and recrystallization process, and the characteristic of recrystallization in Cu-Ni-Fe alloy aged at different temperatures after solution-treatment and cold rolling have been studied by structural analysis and Vickers hardness test. It has shown that the recrystallization of spinodal Cu -Ni-Fe alloy might be divided into 2 types: spinodal decomposition, recovery and recrystallization of two-phase microstructure take place in the deformed alloy aged below the spinodal temperature; while recrystallization of single-phase microstructure and growth of fully-recrystallized grains take place in the deformed alloy aged above the spinodal temperature. The deformed alloy aged below the spinodal temperature recrystallizes in cellular morphology.展开更多
The microstructure of Fe-10Mn-2Cr-1.5C alloy has been investigated with transmission electron microscopy and X-ray diffractometer. The superlattice diffraction spots and satellite reflection patterns have been observe...The microstructure of Fe-10Mn-2Cr-1.5C alloy has been investigated with transmission electron microscopy and X-ray diffractometer. The superlattice diffraction spots and satellite reflection patterns have been observed in the present alloy, which means the appearance of the ordering structure and the modulated structure in the alloy. It is also proved by X-ray diffraction analysis that the austenite in the alloy is more stable than that in traditional austenitic manganese steel. On the basis of this investigation, it is suggested that the C-Mn ordering clusters exist in the austenitic manganese steel and the chromium can strengthen this effect by linking the weaker C-Mn couples together, which may play an important role in work hardening of the austenitic manganese steel.展开更多
文摘Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching would reduce with the increase of Zn content and the precipitation of η-Zn phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD. The microstructure change during aging was observed by TEM.
文摘The interaction of spinodal decomposition and recrystallization process, and the characteristic of recrystallization in Cu-Ni-Fe alloy aged at different temperatures after solution-treatment and cold rolling have been studied by structural analysis and Vickers hardness test. It has shown that the recrystallization of spinodal Cu -Ni-Fe alloy might be divided into 2 types: spinodal decomposition, recovery and recrystallization of two-phase microstructure take place in the deformed alloy aged below the spinodal temperature; while recrystallization of single-phase microstructure and growth of fully-recrystallized grains take place in the deformed alloy aged above the spinodal temperature. The deformed alloy aged below the spinodal temperature recrystallizes in cellular morphology.
文摘The microstructure of Fe-10Mn-2Cr-1.5C alloy has been investigated with transmission electron microscopy and X-ray diffractometer. The superlattice diffraction spots and satellite reflection patterns have been observed in the present alloy, which means the appearance of the ordering structure and the modulated structure in the alloy. It is also proved by X-ray diffraction analysis that the austenite in the alloy is more stable than that in traditional austenitic manganese steel. On the basis of this investigation, it is suggested that the C-Mn ordering clusters exist in the austenitic manganese steel and the chromium can strengthen this effect by linking the weaker C-Mn couples together, which may play an important role in work hardening of the austenitic manganese steel.
