TY - JOUR
T1 - In situ transmission electron microscopy study of ordering in a splat-cooled Ni-20 at.% Mo alloy
AU - Cao, Siqi
AU - Brooks, Charlie R.
AU - Allard, Larry
PY - 1995/3
Y1 - 1995/3
N2 - Using transmission electron microscopy, the microstructure of splat-cooled (through hammer and anvil) Ni-20 at.% Mo specimens has been examined for the as-cooled condition and for heated samples. In the as-cooled condition, the structure consisted of columnar grains with a cell structure of about 0.2nm. The cooling rate was estimated to be about 106 K/s; but even for this rapid cooling, weak short-range order (SRO) was present. Specimens were step-heated in situ in the transmission electron microscope to a specific temperature, held for 5 minutes, cooled to 25 °C for observation, then reheated to a higher temperature, and the process repeated for increasingly higher temperatures. At 500 °C, the intensity of the SRO diffraction spots increased. At 665 °C, these SRO spots split into the long-range order (LRO) positions. At 765 °C, LRO was established with a fine (about 0.05 μm) domain structure. As the heating temperature increased, the cell structure became weak and disappeared at about 765 °C.
AB - Using transmission electron microscopy, the microstructure of splat-cooled (through hammer and anvil) Ni-20 at.% Mo specimens has been examined for the as-cooled condition and for heated samples. In the as-cooled condition, the structure consisted of columnar grains with a cell structure of about 0.2nm. The cooling rate was estimated to be about 106 K/s; but even for this rapid cooling, weak short-range order (SRO) was present. Specimens were step-heated in situ in the transmission electron microscope to a specific temperature, held for 5 minutes, cooled to 25 °C for observation, then reheated to a higher temperature, and the process repeated for increasingly higher temperatures. At 500 °C, the intensity of the SRO diffraction spots increased. At 665 °C, these SRO spots split into the long-range order (LRO) positions. At 765 °C, LRO was established with a fine (about 0.05 μm) domain structure. As the heating temperature increased, the cell structure became weak and disappeared at about 765 °C.
UR - http://www.scopus.com/inward/record.url?scp=0343072385&partnerID=8YFLogxK
U2 - 10.1016/1044-5803(94)00053-N
DO - 10.1016/1044-5803(94)00053-N
M3 - Article
AN - SCOPUS:0343072385
SN - 1044-5803
VL - 34
SP - 87
EP - 95
JO - Materials Characterization
JF - Materials Characterization
IS - 2
ER -