General Research Institute of Non-Ferrous Metals, Beijing,
Pages: 18 Published: Jan 1987
The influence of hydrostatic extrusion on the properties and microstructure of zirconium and Zircaloys has been studied using zirconium and Zircaloy rods produced by cold hydrostatic extrusion and cold drawing. The tensile properties, ductile fracture toughness, microhardness, density, and microvoid content were determined. The microstructural investigations were carried out by metallography, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. It has been found that hydrostatic extrusion increases the strength of zirconium and Zircaloys to some extent and markedly improves their ductilities compared with conventional drawing. The ductile fracture toughness (JIc) and the tear modulus (T) of the extruded material were, respectively, 2 to 3 and 3 to 4 times greater than those of drawn material. Hydrostatic extrusion led to more uniform properties across the whole cross section of the rods and formed a stronger 〈10¯10#x232A; deformation texture, healed the microdefects in the material, increased the density with increasing reduction, formed an unusual substructure through the complete volume, and gave effects similar to those of a fine grain size.
zirconium, Zircaloys, cold hydrostatic extrusion, cold drawing, property, microstructure
Paper ID: STP28114S