Numéro
J. Phys. Colloques
Volume 43, Numéro C4, Décembre 1982
ICOMAT-82
International Conference on Martensitic Transformations
Page(s) C4-169 - C4-172
DOI https://doi.org/10.1051/jphyscol:1982419
ICOMAT-82
International Conference on Martensitic Transformations

J. Phys. Colloques 43 (1982) C4-169-C4-172

DOI: 10.1051/jphyscol:1982419

THE CHARACTERIZATION OF PRETRANSFORMATION MORPHOLOGIES : PERIODIC STRAIN MODULATIONS

L. E. Tanner1, A. R. Pelton2 et R. Gronsky3

1  Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550, U.S.A.
2  Department of Materials Science, Stanford University, Stanford, California 94305, U.S.A.
3  National Laboratory for Electron Microscopy, Materials and Molecular Research Division, Lawrence Berkeley Laboratory, Berkeley, California 94720, U.S.A.


Abstract
The parent cubic phases of alloys which undergo martensitic transformations exhibit various pretransformational effects including the development of fine-scale periodic strain modulations. This diffuse microstructure, revealed by electron microscopy and diffraction, is identified as a dense array of incommensurate shear strains of {110} <[MATH]> type. This behavior, which results in an incipient loss of cubic symmetry, appears to be related to the concurrent parent lattice softening (i.e. the decrease of C' with decreasing temperature approaching Ms) that is observed in most of the same alloys.