Structural evolution of ZA27 alloy
during semi-solid isothermal heat treatment
during semi-solid isothermal heat treatment
(1. School of Materials Science and Engineering,
Gansu University of Technology,Lanzhou 730050, P.R.China;
2. State Key Laboratory for Mechanical Behavior of Materials,
Xi′an Jiaotong University,Xi′an 710049, P.R.China)
Gansu University of Technology,Lanzhou 730050, P.R.China;
2. State Key Laboratory for Mechanical Behavior of Materials,
Xi′an Jiaotong University,Xi′an 710049, P.R.China)
Abstract: The structural evolution of ZA27 alloy modified by element Zr was studied during semisolid isothermal heat treatment, and its transformation mechanism was also discussed. The results indicate that the primary α phase changes from equiaxed grains to spherical grains gradually at semisolid temperature of 460. With increasing isothermal time, the eutectic between boundaries ofα phase diffuses toward α phase, and the primary equiaxed grain arms merge and boundaries tend to disappear to form near particle grains. Further, the eutectic left on α boundaries melts to make the near particle grains separate, and form spherical structure at last.
Key words: ZA27 alloy; semi-solid state; isothermal heat treatment; structural evolution; spherical structure