The purpose of the present work is to investigate the effect of
microstructural variations of the annealed (Pb-1.5 wt % Sb) alloy during the
phase transformation, on their mechanical and electrical properties. Creep < br />tests on the studied alloy (slow cooled) were made under different constant
stresses ranging from 12 M Pa to 15 M Pa near the transformation
temperature. Transient and steady state creep of this alloy showed a transition
point at 443K. The transient creep parameters (β and n) were found to change
with the applied stress and ageing temperature. The value of the time
exponent(γ ) was found to be 0.45, the activation energy of both the transient
and steady state creep was found to be 42 kJ/mole and 52kJ/mole respectively
above 443K. It was found that the strain rate sensitivity parameter (m) has the
values ranging from 0.17 to 0.35. The microstructure of the deformed alloy
samples were investigated by : X-ray diffraction technique which showed that
the residual internal lattice strain was at 443K. Transmission electron
microscopy and electron diffraction results showed good agreement with the Xray
analysis. The dependence of the resistivity changes on the ageing
temperatures were also studied. The activation energy of the precipitation
process was found to be ranged from 0.07 to 0.09 ev, below and above 443K
respectively.