X-RAY STUDY OF WIRE-DRAWN NIOBIUM AND TANTALUM

摘要

The material Table I This increase is a consequence of the work hardening associated with plastic deformation which, however, invariably reduced the ductility of the material. The drawing operation involves a number of processing variables such as-the die angle, the type of lubrication, the reduction per draw, the draw direction with respect to the previous pass, and the rate of drawing. However, the drawing process basically consists of applying to the metal surface large shear forces which reduce the wire or rod diameter by causing an axial plastic flow of the surface;there is also, with increasing severity of the draw (i.e. percent reduction in cross-sectional area per pass) a progressive radial penetration of cold work into the wire.