Patent ID: 7485198

Claim:
A process for making an extruded tantalum billet, comprising extruding a tantalum ingot having a cylindrical shape having a cross section with a diameter of 6 inches to about 14 inches and having a metal purity of at least 99.99% at a sufficient temperature and for a sufficient time to at least partially recrystallize the tantalum billet during extrusion and form said extruded tantalum billet having a cylindrical shape with an aspect ratio L/D greater than 0.5 with a reduced diameter of 3½ inches or greater and a substantially uniform grain size throughout the cross section of the extruded tantalum billet from said extruding, and said extruded tantalum billet has an average grain size throughout the cross section of the extruded tantalum billet of about 150 microns or less, and said extruded tantalum billet is about 98% or more recrystallized.