Pilger tooling design for texture control

It has been shown earlier that the crystallographic texture of a Zircaloy tube is determined by the ratio of wall reduction to diameter reduction during tube fabrication. The use of this ratio as applied mathematically to the starting tube size and the final tube size does not take into account the complex nature of the tapers in the tube reducing tooling. Instantaneous values of the reduction ratio along the tube transition are shown to vary widely in tools of conventional design. A tooling design scheme that holds the reduction or strain ratio constant is developed by mathematical integration of the basic premise. Data showing the results of various reductions made holding the reduction ratio constant are shown. These tests indicate that the texture rotation is not a linear function of the reduction ratio, and there is a strong indication that the strain field is not homogeneous in thick-walled tubes.