Abstract
The creep of a Cu-2·5 at.pct. Al alloy has been investigated by the isothermal tests technique. Two dislocation mechanisms operate in parallel in the investigated temperature region. In the region of lower minimum creep rates (\(\dot \varepsilon \)<3×10−5 sec−1) — region 1 — the activation energy of creep is close to the expected value of the activation enthalpy of the lattice self-diffusion of copper in the alloy. The stress dependence of the minimum creep rate can be described by a power function of theσ n type, where n=n1=5·8. The results for region 1 can be satisfactorily correlated with the model of nonconservative motion of jogs on screw dislocations dependent on lattice self-diffusion. If a power function of theγ m type is used to describe the minimum creep rate dependence on the stacking fault energyγ, thenm is equal to −0.66.
In the region of higher minimum creep rates — region 2 — the apparent activation energy is higher than the expected value of the activation enthalpy of lattice self-diffusion of any component in the investigated alloy. The dislocation mechanism dominating in region 2 has not been identified.
The influence of stacking fault energy on the minimum creep rate in region 2 is weak or even zero.
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Pahutova, M., Hostinsky, T., Čadek, J. et al. Creep of a Cu-2·5 at. pct. Al alloy at high temperatures. Czech J Phys 19, 1214–1228 (1969). https://doi.org/10.1007/BF01690307
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DOI: https://doi.org/10.1007/BF01690307