Mechanical Equation of State in an Al-Li Alloy

Existence of plastic equation of state has been investigated by performing a series of load relaxation tests at various temperatures using an Al-Li alloy. A plastic equation of state is first developed from a simple kinetics consideration for a mechanical activation process of a leading dislocation piled up against grain boundaries. A series of load relaxation test has been conducted at temperatures ranging from 200 to 530oC to obtain the stress-strain rate curves. A plastic equation of state has been derived from a simple consideration of dislocation kinetics and confirmed by experimental results.





References:
[1] E.W. Hart,Acta Metall., vol. 18, p. 599, 1970.
[2] J. Cadek, Creep in Metallic Materials, Elsevier Sci. Pub. Co., p. 14,
1988.
[3] E.W. Hart and H.D. Solomon,Acta Metall., vol. 21, p. 295, 1973.
[4] G.L. Wire, H. Yamada and Che-Yu Li,Acta Metall., vol. 22, p.
505,1974.
[5] H. Yamada and Che-Yu Li, Metall. Trans., vol. 4A, p. 2133, 1973.
[6] Y.W. Chang and E. C. Aifantis, Constitutive Laws for Engineering
Materials, Ed. C.S. Desai et al., Elsevier Sci. Pub. Co., p. 293 1987.
[7] E.Kroener, Physics of Defects, North-Holland, p. 215 ,1981.
[8] E.W. Hart, J. Eng. Mater. Tech., vol. 106, p. 322, 1984. [9] J. A. Wert, N. E. Paton, C. H. Hamilton, and M. W. Mahoney, Metall.
Trans., vol. 12A, pp. 1267-1276, 1981.
[10] B.R.Lawn and T.R. Wilsaw, Fracture of Brittle Solid, Cambridge Univ.
Press, p. 28, 1975.
[11] D.Lee and E.W. Hart, Metall. Trans., vol. 2A, p. 1245, 1971.
[12] K. Honda,Jap.J.Appl.Phys.,vol. 27, p. 2232, 1988.
[13] R. Raj, and M. F. Ashby, Metall. Trans., vol. 2A, pp. 1113-1127, 1971.