Kinetics of long-range order relaxation in Ni{sub 3}Al: The effect of stoichiometry

Journal Article · Mon Apr 01 00:00:00 EST 1996 · Acta Materialia

DOI:https://doi.org/10.1016/1359-6454(95)00298-7· OSTI ID:230804

Dimitrov, C; Zhang, X; Dimitrov, O ^[1]

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1. CECM-CNRS, Vitry sur Seine (France)

The isothermal relaxation of long-range order (LRO) after small temperature changes has been investigated in Ni{sub 3}Al intermetallic compounds (with 24.6, 25.0 and 26.5 at% Al) by measurements of the residual electrical resistivity. The equilibrium residual electrical resistivities were found to be consistent with theoretically calculated values of the LRO parameter. The approach to equilibrium could be satisfactorily represented by a sum of two exponentials; the relaxation rate is minimum at the stoichiometric composition. The activation enthalpies of the two processes are not significantly different (2.63--2.88 eV); they do not display an important composition dependence. A model is proposed for explaining the existence of the two isothermal relaxation processes.

• OSTI ID: 230804
• Journal Information: Acta Materialia, Vol. 44, Issue 4; Other Information: PBD: Apr 1996
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
NICKEL ALLOYS
ORDER PARAMETERS
ALUMINIUM ALLOYS
BINARY ALLOY SYSTEMS
INTERMETALLIC COMPOUNDS
CHEMICAL COMPOSITION
ELECTRIC CONDUCTIVITY
EQUILIBRIUM
TEMPERATURE DEPENDENCE
ACTIVATION ENERGY
CORRELATIONS
SELF-DIFFUSION