Summary: published in MRS Symp. Proc. on Nanophase and Nanophase Composites III (S. Komarneni, J.C. Parker, and H.
Hahn, eds.) Mater. Res. Soc. Symp. Proc. 581, Warrendale, PA (1999).
MORPHOLOGICAL STABILITY OF Ni(Al)/Ni3Al NANOLAMINATE COMPOSITES
JASON P. FAIN*, RAJARSHI BANERJEE*, DANIEL JOSELL**, PETER M. ANDERSON*,
HAMISH FRASER*, NATALIA TYMIAK***, AND WILLIAM GERBERICH***
*Dept. MSE, The Ohio State University, 2041 College Rd., Columbus, OH 43210-1179,
**Materials B164 NIST 100 Bureau Dr, Stop 8554 Gaithersburg, MD 20899-8554.
***Dept. of Chemical Eng. and Materials Science, University of Minnesota, Minneapolis, MN.
This manuscript discusses the morphological instability observed when multilayered
samples with alternating layers of g-Ni(Al)/g'-Ni3Al are exposed to 800C for approximately 100
hours. Samples with 20nm/20nm or 120nm/120nm layer thickness and <001> or <111> crystal
orientation to the interface normal were tested. Pinching off of layers is strongly affected by
crystal orientation and layer thickness. Corresponding modeling suggests that the stability of this
system is sensitive to fluctuations in the volume fraction of the two phases, the aspect ratio of
columnar grains in the layers, and whether coherent or semi-coherent interfaces are present.
Nanolayered materials consisting of alternating A/B type layers of metals exhibit large
values of hardness that increase monotonically as individual layer thickness is decreased .