TEXTURE OF HYDROSTATICALLY EXTRUDED Zr-2.5% Nb ALLOY TUBE

The pole figure and inverse pole figure of the hydrostatically extruded Zr-2.5%Nb alloy tube with various Q values (the reduction ratio of wall thickness to diameter) were examined by X-ray diffration. It is resulted that the texture parameter, V_48 is related linearly to Q value. The texture gradient along the direction of tube wall thickness seems to be no appreciable. When the Q value changes from 0.2 to 2.59, the hydride is distributed into a circular direction via radial, and the corresponding texture parameter V_48 decreases from 0.53 to 0.28.The circular hydride distribution may be re-orientated under circular tensile stress after cyclic heat-treatment. The threshold of the stress re-orientaton of hydrideis rather high for tube with radial basal pole texture.