  The {\alpha}+\b{eta} titanium alloy (Ti6Al4V) has been successfully joined
using rotary friction welding. To investigate the influence of post weld heat
treatments on the microstructure and mechanical properties of the welds, the
weld joints were heat treated in {\alpha}+\b{eta} and \b{eta} regions, followed
by air cooling and furnace cooling. Subsequent to heat treatment, the specimens
were subjected to stress relieving treatment. The heat treatment temperatures
were selected keeping in view the beta transus temperature of the alloy.
Mechanical properties of the welds are evaluated in the as-welded and post weld
heat treated conditions at the working temperature of this alloy. The results
reported are an average of the values obtained from three tests carried out at
a given set of condition. Joints produced exhibited better mechanical
properties when compared to the parent metal. Coarse transgranular
microstructure and coarse grains in general exhibit better creep and stress
rupture properties, while finer microstructures exhibit better tensile
strengths
