| A new interpretation for the anomalous yield phenomena has been suggested from an internal variable approach. The high temperature deformation behavior of β-CuZn alloy(B2 structure) has been investigated through a series of load relaxation tests and analyzed by the inelastic deformation theory. The high temperature deformation behavior of β-CuZn alloy is well described by inelastic deformation theory, consisting of three deformation modes, internal, plastic and dislocation creep deformation modes. Among the above three modes, inelastic deformation has proved to be the most important one to affect the anomalous phenomena. It has also been proposed that the anomalous phenomena can only occur when the reference strain rate(ε˙_o) at higher temperature falls into the lower strain rate and lower stress region. The activation energy for dislocation creep is obtained as 159 kJ/mole, similar to that for the self diffusion of Cu or Zn. It is therefore thought here that the decrease of yield stress above T_p in tensile test is mainly due to dislocation climb process. |
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