Abstract
SAP-type alloys, which are obtained directly by powder metallurgy, consist of a dispersion of alumina particles in a polycrystalline aluminum matrix.
The kinetics of the deformation of these alloys has been studied by tensile tests. These tests, classical and differential, permit the determination of the activation energy and of the activation volume over a wide range of temperatures and stresses.
At low temperatures, from —196 to 20°C., the deformation mechanism is the thermally activated intersection of dislocations in the aluminum matrix. The density of dislocations increases rapidly with the strain and leads to high strain-hardening rates. At higher temperatures the dislocations move by cross-slip and by self-diffusion in the matrix. For temperatures above 350°C the apparent activation energy increases to very large values. Two models are proposed to explain this phenomenon: (1) a pinning of dislocations by the alumina particles; (2) reactions of attractive dislocations in those grains where there is still a high dislocation density. The grain size seems to have no influence.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Ruedl, E., and P. Guyot, “Electron Microscopy of SAP Following Tensile Deformation or Quenching,” this volume, pp. 131–144.
Fullman, R. L., Trans. AIME 197:447 (1953).
Guyot, P., Doctoral thesis (1965) (to be published).
Kelly, A., and R. B. Nicholson, Progr. Mater. Sci. 10 (3) (1963).
Seeger, A., Dislocations and Mechanical Properties of Crystals, John Wiley and Sons, Inc. (New York), 1957, p. 243.
Friedel, J., Dislocations, Pergamon Press, Inc. (New York), 1964.
Saada, G., Métaux et Corrosion (July-August-September 1960).
Basinsky, Z. S., Phil. Mag. 4: 393 (1959).
Guyot, P., and R. Debeir, Acta Met. 14: 43 (1966).
Mitchell, J. B., S. K. Mitra, and J. E. Dorn, Trans. Quarterly (June 1963), p. 263.
Sherby, O., J. L. Lytton, and J. E. Dorn, Acta Met. 5: 219 (1957).
Walton, D., L. Shepard, and J. E Dorn, Trans. AIME 221: 458 (1961).
Meyers, C. L., J. C. Shyne, and O. D. Sherby, DMS Report No. 62. 10, Stanford University, California (1962).
Lenel, F. V., and G. S. Ansell, in: Powder Metallurgy, Interscience (New York), 1962, p. 267.
Thomas, G., and N. J. Nutting, J. Inst. Metals 86: 7 (1957).
Weertman, J., J. Appl. Phys. 26: 1213 (1955).
Hirsch, P. B., and D. H. Warrington, Phil. Mag. 6: 735 (1961).
Guyot, P., Acta Met. 12: 941 (1964).
Hirsch, P. B., Internal Stress and Fatigue in Metals, Elsevier (Amsterdam), 1959.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1966 Springer Science+Business Media New York
About this chapter
Cite this chapter
Guyot, P. (1966). On the Mechanisms of Plastic Deformation of SAP-Type Alloys. In: Hausner, H.H. (eds) Modern Developments in Powder Metallurgy. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-7882-2_8
Download citation
DOI: https://doi.org/10.1007/978-1-4684-7882-2_8
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4684-7884-6
Online ISBN: 978-1-4684-7882-2
eBook Packages: Springer Book Archive