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Title: Morphological evolution of coherent multivariant Ti{sub 11}Ni{sub 14} precipitates in Ti-Ni alloys under an applied stress -- A computer simulation study

Journal Article · · Acta Materialia
;  [1]
  1. Pennsylvania State Univ., University Park, PA (United States). Dept. of Materials Science and Engineering

Coherent precipitation of multi-variant Ti{sub 11}Ni{sup 14} precipitates in TiNi alloys was investigated by employing a continuum field kinetic model. The structural difference between the precipitate phase and the matrix as well as the orientational differences between precipitate variants are distinguished by nonconserved structural field variables, whereas the compositional difference between the precipitate and matrix is described by a conserved field variable. The temporal evolution of the spatially dependent field variables is determined by numerically solving the time-dependent Ginzburg-Landau (TDGL) equations for the structural variables and the Cahn-Hilliard diffusion equation for the composition. In particular, the interaction between precipitates, and the growth morphology of Ti{sub 11}Ni{sub 14} precipitates under strain-constraints were studied, without a priori assumptions on the precipitate shape and distribution. The predicted morphology and distribution of Ti{sub 11}Ni{sub 14} variants were compared with experimental observations. Excellent agreement between the simulation and experimental observations was found.

OSTI ID:
616200
Journal Information:
Acta Materialia, Vol. 46, Issue 2; Other Information: PBD: 5 Jan 1998
Country of Publication:
United States
Language:
English