TY - JOUR
T1 - On the crystal structure of Cr2N precipitates in high-nitrogen austenitic stainless steel. II.1 Order-disorder transition of Cr 2N during electron irradiation
AU - Lee, Tae Ho
AU - Kim, Sung Joon
AU - Takaki, Setsuo
PY - 2006/4/1
Y1 - 2006/4/1
N2 - The crystal structure and order-disorder transition of Cr2N were investigated utilizing transmission electron microscopy (TEM). Based on the analyses of selected-area diffraction (SAD) patterns, the crystal structure of the ordered Cr2N superstructure was confirmed to be trigonal (P̄31m), characterized by three sets of superlattice reflections (001), (11/33 0) and (11/33 1). During electron irradiation, the superlattice reflections gradually disappeared in the regular sequence (001), (11/33 0) and (11/33 1), indicating that the order-disorder phase transition of Cr 2N occurred. The convergent-beam electron diffraction (CBED) observation revealed that the space group of disordered Cr2N is P62/mmc, which corresponds to an h.c.p. (hexagonal close packed) sublattice of metal atoms with a random distribution of N atoms in six octahedral interstices. The redistribution model of N atoms through the order-disorder transition is discussed based on the characteristics and disappearing sequence of superlattice reflections.
AB - The crystal structure and order-disorder transition of Cr2N were investigated utilizing transmission electron microscopy (TEM). Based on the analyses of selected-area diffraction (SAD) patterns, the crystal structure of the ordered Cr2N superstructure was confirmed to be trigonal (P̄31m), characterized by three sets of superlattice reflections (001), (11/33 0) and (11/33 1). During electron irradiation, the superlattice reflections gradually disappeared in the regular sequence (001), (11/33 0) and (11/33 1), indicating that the order-disorder phase transition of Cr 2N occurred. The convergent-beam electron diffraction (CBED) observation revealed that the space group of disordered Cr2N is P62/mmc, which corresponds to an h.c.p. (hexagonal close packed) sublattice of metal atoms with a random distribution of N atoms in six octahedral interstices. The redistribution model of N atoms through the order-disorder transition is discussed based on the characteristics and disappearing sequence of superlattice reflections.
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U2 - 10.1107/S0108768106003338
DO - 10.1107/S0108768106003338
M3 - Article
C2 - 16552151
AN - SCOPUS:33645314354
SN - 0108-7681
VL - 62
SP - 190
EP - 196
JO - Acta Crystallographica Section B: Structural Science
JF - Acta Crystallographica Section B: Structural Science
IS - 2
ER -