Grain refinement of commercial purity zirconium by equal channel angular pressing

Abstract

To develop an ultrafine grain structure in commercial purity zirconium, equal channel angular ECA pressing was carried out at room temperature by varying the number of passes and the rotation methods. It was possible to reduce the grain size to 0.2 μm without fracture of the specimen by the imposition of severe plastic straining on commercial purity zirconium via ECA pressing. Grain size decreased and misorientation between grains increased with increasing number of ECA pressing passes, using processing route B_A in which the specimen was rotated by 90° in the same direction between each consecutive pass through the ECA pressing die.