This paper describes our preliminary results by using electron backscatter diffraction(EBSD) attachment in a scanning electron microscope. These studies revealed that the basal plane of 2H martensite originates from o...This paper describes our preliminary results by using electron backscatter diffraction(EBSD) attachment in a scanning electron microscope. These studies revealed that the basal plane of 2H martensite originates from one {220} P plane of the parent phase, four variants A,B,C,D of a self accommodating plate group originate from various {220} P planes of the parent phase. Their orientation relationships can be determined by EBSD technique. The structural information provided by EBSD technique together with the composition information provided by energy dispersive X ray spectrometer leads to much convincible identification of micro area phases. By this method three phases were identified in as cast Al Cu Fe alloys with composition near that of icosahedral quasicrystal(IQC), namely IQC, λ Al 13 Fe 4 and β phases. Two types of grains were found in an interstitial free steel recrystallized at 750℃.Among them the flat grains possess γ fibre microtexture benifitial to the cold workability.展开更多
The sampled-grating distributed Bragg reflector(SGDBR) laser is a typical and important photonic integrated device,and has potential wide application to agile optical networks.A new dynamic model for this device has b...The sampled-grating distributed Bragg reflector(SGDBR) laser is a typical and important photonic integrated device,and has potential wide application to agile optical networks.A new dynamic model for this device has been developed,which combines the traveling-wave method for the active region and the transfer-matrix method for the passive sections into a single procedure.The behaviors of wave-length switching of the SGDBR laser,which include the transient spectrum and mode competition,have been studied in detail using this model.A new efficient way has been proposed to improve the wavelength switching performance only by increasing the coupling coefficients without changing the carrier density.展开更多
文摘This paper describes our preliminary results by using electron backscatter diffraction(EBSD) attachment in a scanning electron microscope. These studies revealed that the basal plane of 2H martensite originates from one {220} P plane of the parent phase, four variants A,B,C,D of a self accommodating plate group originate from various {220} P planes of the parent phase. Their orientation relationships can be determined by EBSD technique. The structural information provided by EBSD technique together with the composition information provided by energy dispersive X ray spectrometer leads to much convincible identification of micro area phases. By this method three phases were identified in as cast Al Cu Fe alloys with composition near that of icosahedral quasicrystal(IQC), namely IQC, λ Al 13 Fe 4 and β phases. Two types of grains were found in an interstitial free steel recrystallized at 750℃.Among them the flat grains possess γ fibre microtexture benifitial to the cold workability.
基金Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA03Z427)State Key Development Program for Basic Research of China (Grant No. 2003CB314903)National Natural Science Foun-dation of China (Grant No. 60677024)
文摘The sampled-grating distributed Bragg reflector(SGDBR) laser is a typical and important photonic integrated device,and has potential wide application to agile optical networks.A new dynamic model for this device has been developed,which combines the traveling-wave method for the active region and the transfer-matrix method for the passive sections into a single procedure.The behaviors of wave-length switching of the SGDBR laser,which include the transient spectrum and mode competition,have been studied in detail using this model.A new efficient way has been proposed to improve the wavelength switching performance only by increasing the coupling coefficients without changing the carrier density.
