Hot Working of Zirconium Alloys: Some Recent Developments

Abstract

The published results on the hot deformation behaviour of zirconium and its alloys have been reviewed critically to ascertain the type of information available in the areas of hot workability and evolution of microstructure during hot deformation. It is observed that in a majority of these investigations, the emphasis was on the fundamental aspects of hot deformation such as identification of the rate controlling mechanisms, activation energy for hot working and identification of softening mechanisms. However, no systematic effort has been directed towards the optimization of hot workability and control of microstructure of these technologically important materials. In recent years efforts have been made to characterize the hot workability and development of microstructure during hot deformation by constructing power dissipation maps or processing maps and flow instability maps in the format of Dynamic Materials Model. The power dissipation maps and instability maps have been found very useful in optimizing the hot workability and controlling the microstructure during hot deformation of several zirconium alloys.

Keywords:

• Zirconium alloys
• Hot working
• Processing map
• Dynamic recrystallization
• Flow localization