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Materialien/Werkstoffe Poster: Do., 13:00–15:30 D-P378
Crystallographic texture investigations of Cu-Nb tubes for industrial applications
Heinz-Günter Brokmeier 1 , Wenhai Ye 1 , Waldemar Singer, Xenia Singer
1 IWW - Technische Universität Clausthal / GKSS-Forschungszentrum, Max-Planck-
Str, 21502 Geesthacht – 2 DESY-MPL, Notke-Str.85, 22607 Hamburg
Cu- Nb tubes are one of the candidates for the manufacturing of accelerator units
for a linear collider. In order to produce an accelerator unit by hydro-forming the
Cu-Nb tube is the pre-product which should have homogeneous textures around the
perimeter. Beside the type of the initial materials such as the Cu and the Nb alloy
and the production of the pure Cu and the pure Nb tubes the joining technique to
form a Cu-Nb tube composite is of basic interest. The present investigation deals with
co-extruded and explosive bonded material with a final wall thickness of about 4 mm
(Cu 3 mm thick and Nb 1 mm thick). Non-destructive measurements were carried out
on one hand to determine the texture inhomogeneity using thermal neutrons and on
the other hand to study the strain gradient over the tube thickness using synchrotron
radiation. This contribution will focus on the crystallographic texture. Therefore ring
samples were cut samples with a diameter of 140 mm and a width of 15 mm. Due to
the high penetration depth of thermal neutrons the average texture of both phases was
measured. In order to get local textures around the perimeter of the Cu-Nb ring a
Cd-slit for the incoming beam and a similar Cd-slit for the outgoing beam were used.
In both phases typical textures types of fcc-Cu and bcc-Nb were found. By calculating
the orientation distribution function using ISEM (iterative serious expansion method)
one is able to compare quantitatively textures correlated to the processing technique, to
describe texture variations along the perimenter and to study textures changes during
thermo-mechanical treatments (heating, cooling etc.)