Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns...Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers.展开更多
Phase equilibria in the Fe-Nb-Zr system at 1,200 ℃ were determined by X-ray diffraction （XRD） and scanning electron microscope （SEM） coupled with energydispersive X-ray spectroscopy （EDS） techniques. Extensive ...Phase equilibria in the Fe-Nb-Zr system at 1,200 ℃ were determined by X-ray diffraction （XRD） and scanning electron microscope （SEM） coupled with energydispersive X-ray spectroscopy （EDS） techniques. Extensive NbFez domain was proposed in the current work. This compound existed in the composition range from 35 at% to 73 at% Fe, 12 at% to 32 at% Nb, and 0 to 32 at% Zr. In the present work, four three-phase regions （1）-（Nb,Zr） ＋ NbFe ＋ NbFe2, （2） [3-（Nb,Zr） ＋ NbFe2 ＋ Liquid, （3） NbFe2 ＋ Liquid ＋ ZrFe2, and （4） ZrFe2 ＋ Fe ＋ NbFe2, were established.展开更多
Microstructure and phase transformation in the Al-Cu-Fe alloys of the approximate compositional range of 20 - 50 at.% Cu and 2 - 10 Fe at.% have been investigated from samples quenched from their respective temperatur...Microstructure and phase transformation in the Al-Cu-Fe alloys of the approximate compositional range of 20 - 50 at.% Cu and 2 - 10 Fe at.% have been investigated from samples quenched from their respective temperatures by means of different thermal analysis, magnetothermal analysis, scanning electron microscopy, electron probe analysis and powder X-ray diffraction. Representative phase transformations categorized as polymorphic, discontinuous precipitation, quasi-binary eutectoid, and ternary transitional U-type phase transformation are presented. These phase transformations were found to have a common feature which consumes the phase and appears the phase. A schematic diagram was proposed to demonstrate the transition processes with decreasing temperature.展开更多
文摘Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers.
基金supported by the National Natural Science Foundation of China(No.51001033)the Natural Science Foundation of Guangxi(No.2011GXNSFA018030)+2 种基金the Program for Excellent Talents in Guangxi Higher Education InstitutionsScience Research Program for Education Department of Guangxi(No.2011LX140)the Science Foundation of Guangxi University for Nationalities(Nos.2008ZD010,2010ZD012,2011QD019,and 2011MDQN046)
文摘Phase equilibria in the Fe-Nb-Zr system at 1,200 ℃ were determined by X-ray diffraction （XRD） and scanning electron microscope （SEM） coupled with energydispersive X-ray spectroscopy （EDS） techniques. Extensive NbFez domain was proposed in the current work. This compound existed in the composition range from 35 at% to 73 at% Fe, 12 at% to 32 at% Nb, and 0 to 32 at% Zr. In the present work, four three-phase regions （1）-（Nb,Zr） ＋ NbFe ＋ NbFe2, （2） [3-（Nb,Zr） ＋ NbFe2 ＋ Liquid, （3） NbFe2 ＋ Liquid ＋ ZrFe2, and （4） ZrFe2 ＋ Fe ＋ NbFe2, were established.
文摘Microstructure and phase transformation in the Al-Cu-Fe alloys of the approximate compositional range of 20 - 50 at.% Cu and 2 - 10 Fe at.% have been investigated from samples quenched from their respective temperatures by means of different thermal analysis, magnetothermal analysis, scanning electron microscopy, electron probe analysis and powder X-ray diffraction. Representative phase transformations categorized as polymorphic, discontinuous precipitation, quasi-binary eutectoid, and ternary transitional U-type phase transformation are presented. These phase transformations were found to have a common feature which consumes the phase and appears the phase. A schematic diagram was proposed to demonstrate the transition processes with decreasing temperature.
