The specimens were implanted with aluminum ions with fluence ranging from 1× 10^16 to 1× 10^17 ions/cm^2 to study the effect of aluminum ion implantation on the aqueous corrosion behavior of zircaloy-2 by me...The specimens were implanted with aluminum ions with fluence ranging from 1× 10^16 to 1× 10^17 ions/cm^2 to study the effect of aluminum ion implantation on the aqueous corrosion behavior of zircaloy-2 by metal vapor vacuum arc source （MEVVA） at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy （XPS） and Auger electron spectroscopy （AES）, respectively. Transmission electron microscopy （TEM） was used to examine the microstructure of the aluminum-implanted samples. Glancing angle X-ray diffraction （GAXRD） was employed to examine the phase transformation due to the aluminum ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted zircaloy-2 in a 1 M H2SO4 solution. It is found that a significant improvement was achieved in the aqueous corrosion resistance of zircaloy-2 implanted with aluminum ions. Finally, the mechanism of the corrosion behavior of aluminum- implanted zircaloy-2 was discussed.展开更多
The precipitation process of zirconium hydrides induced by stress and strain was investigated by means of electron microscopy in-situ.The precipitating hydrides induced by stress were found to be γ phase with orienta...The precipitation process of zirconium hydrides induced by stress and strain was investigated by means of electron microscopy in-situ.The precipitating hydrides induced by stress were found to be γ phase with orientation relationship of (110)_γ‖(110)_(αZr),(001)_γ‖ (0001)_(αZr) between γ-hydrides and surrounding matrix.The growth rate of γ-hydrides which was much faster along [110] direction brought them in taper shape.After fracture of y-hydrides,a new one will precipitate at the tip of cracks.This is the essential process of hydrogen-induced delayed cracking in Zircaloy.The precipitating hydrides induced by strain were found to be δ phase with both orientation relationships of(111)_δ‖(0001)_(αZr),(110)_δ‖ (110)_(αZr) or (010)_δ‖(0001)_(αZr),(001)_δ‖(110)_(αZr)between δ-hydride and surrounding matrix.The δ-hydrides become much finer as the strain rate increased.展开更多
基金the National Natural Science Foundation of China (No.50501011, G 2000067207-1)Postdoctoral Research Foundation of China (37th batch, No.2005037079)
文摘The specimens were implanted with aluminum ions with fluence ranging from 1× 10^16 to 1× 10^17 ions/cm^2 to study the effect of aluminum ion implantation on the aqueous corrosion behavior of zircaloy-2 by metal vapor vacuum arc source （MEVVA） at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy （XPS） and Auger electron spectroscopy （AES）, respectively. Transmission electron microscopy （TEM） was used to examine the microstructure of the aluminum-implanted samples. Glancing angle X-ray diffraction （GAXRD） was employed to examine the phase transformation due to the aluminum ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted zircaloy-2 in a 1 M H2SO4 solution. It is found that a significant improvement was achieved in the aqueous corrosion resistance of zircaloy-2 implanted with aluminum ions. Finally, the mechanism of the corrosion behavior of aluminum- implanted zircaloy-2 was discussed.
文摘The precipitation process of zirconium hydrides induced by stress and strain was investigated by means of electron microscopy in-situ.The precipitating hydrides induced by stress were found to be γ phase with orientation relationship of (110)_γ‖(110)_(αZr),(001)_γ‖ (0001)_(αZr) between γ-hydrides and surrounding matrix.The growth rate of γ-hydrides which was much faster along [110] direction brought them in taper shape.After fracture of y-hydrides,a new one will precipitate at the tip of cracks.This is the essential process of hydrogen-induced delayed cracking in Zircaloy.The precipitating hydrides induced by strain were found to be δ phase with both orientation relationships of(111)_δ‖(0001)_(αZr),(110)_δ‖ (110)_(αZr) or (010)_δ‖(0001)_(αZr),(001)_δ‖(110)_(αZr)between δ-hydride and surrounding matrix.The δ-hydrides become much finer as the strain rate increased.
