TY - JOUR
T1 - Transmission electron microscopy study of unhydrided,dehydrided and annealed LaNi5
AU - Veirman, de, A.E.M.
AU - Staals, A.A.
AU - Notten, P.H.L.
PY - 1994
Y1 - 1994
N2 - The influence of hydrogen absorption on the microstructure of LaNi5 powders
has been investigated by transmission electron microscopy. At the surface of the
unhydrided and dehydrided LaNi5 grains a reaction layer is observed. By means of
selected area electron diffraction this layer is found to consist of metallic nickel and
a second constituent, most probably La203. This observation suggests that this
surface layer is not induced by the hydrogen absorption reaction. Within dehydrided
LaNi5 grains planar-like defects, which are formed during previous hydrogen
absorption, were observed. The habit plane, strain field and average spacing of these
planar-like defects have been determined. From the correspondence between the
above characteristics and the reduced coherence length perpendicular to the c-axis,
as derived from anisotropic peak broadening in X-ray diffraction analyses, it was
concluded that a correlation exists between the presence of planar-like defects and
peak broadening. This correlation is further sustained by the fact that they both
disappear upon annealing at 600°C.
AB - The influence of hydrogen absorption on the microstructure of LaNi5 powders
has been investigated by transmission electron microscopy. At the surface of the
unhydrided and dehydrided LaNi5 grains a reaction layer is observed. By means of
selected area electron diffraction this layer is found to consist of metallic nickel and
a second constituent, most probably La203. This observation suggests that this
surface layer is not induced by the hydrogen absorption reaction. Within dehydrided
LaNi5 grains planar-like defects, which are formed during previous hydrogen
absorption, were observed. The habit plane, strain field and average spacing of these
planar-like defects have been determined. From the correspondence between the
above characteristics and the reduced coherence length perpendicular to the c-axis,
as derived from anisotropic peak broadening in X-ray diffraction analyses, it was
concluded that a correlation exists between the presence of planar-like defects and
peak broadening. This correlation is further sustained by the fact that they both
disappear upon annealing at 600°C.
U2 - 10.1080/01418619408242934
DO - 10.1080/01418619408242934
M3 - Article
SN - 0141-8610
VL - 70
SP - 837
EP - 849
JO - Philosophical Magazine A : physics of condensed matter, structure, defects and mechanical properties
JF - Philosophical Magazine A : physics of condensed matter, structure, defects and mechanical properties
IS - 5
ER -