Apparent activation energy of eutectoid transformation in wrought ZA16 alloy was examined by thermal analysis with temperature-increment during squeezing casting.The relationship between thermal stability and microstructure evolution of the alloy after heat treatment was described.The activation energy and thermal stability of the alloy are decreased with the increase of deformation rate.After annealing treatment

the hardness of the as-cast alloy is reduced

and that of wrought alloy is obviously increased.The work-softening and annealing-hardening are observed in the deformed ZA16 alloy resulted from the broken coarsened grain during processing which allow more deformation rate to the material.Precipitated structure along the working direction after annealing treatment restrains the grain rotary in spheroidized structure for coordinated deformation

which is responsible for the annealed-hardening.