Processing of Hollow Sections

Abstract

A system and method provide a material with uniform micro-structure. In an embodiment, an equal channel angular extrusion system includes an interior mandrel. The interior mandrel includes an expanding shear material section and a contracting shear material section. In addition, the system includes a material. The material is disposed about a portion of the interior mandrel. Moreover, the system includes a pressure application device. The pressure application device applies pressure to the material to force the material to contact the expanding shear material section to provide an expanded post-shear material section. Pressure from the pressure application device applies pressure to the material to force the expanded post-shear material section to contact the contracting shear material section to provide a contracted shear material section.

What is claimed is: 
     
         1 . An equal channel angular extrusion system, comprising:
 a mandrel,
 wherein the mandrel is hollow and comprises a mandrel pre-shear zone section and a mandrel post-shear zone section, 
 wherein the mandrel post-shear zone section is at an angle to the mandrel pre-shear zone section, 
 wherein a shear zone extends laterally across the mandrel at the intersection of the mandrel pre-shear zone section and the mandrel post-shear zone section, and 
 wherein the angle is between 90 degrees and 180 degrees; 
   a material,
 wherein the material is any material suitable for severe plastic deformation; 
   a pressure application device,
 wherein the pressure application device is any device capable of supplying a sufficient pressure to the material to force the material through the mandrel; and 
   a lubricant,
 wherein the lubricant is applied to an exterior surface of the material prior to the material being disposed in the mandrel. 
   
     
     
         2 . The equal channel angular extrusion system of  claim 1 , wherein the material comprises a metal. 
     
     
         3 . The equal channel angular extrusion system of  claim 2 , wherein the metal comprises a transition metal, a metal alloy, or combinations thereof. 
     
     
         4 . The equal channel angular extrusion system of  claim 2 , wherein the metal comprises niobium. 
     
     
         5 . The equal channel angular extrusion system of  claim 2 , wherein the metal comprises tantalum. 
     
     
         6 . The equal channel angular extrusion system of  claim 1 , wherein, wherein the material is hollow. 
     
     
         7 . The equal channel angular extrusion system of  claim 1 , wherein the material is solid. 
     
     
         8 . The equal channel angular extrusion system of  claim 1 , wherein the material has a cross sectional shape which is circular, hexagonal, octagonal, or square. 
     
     
         9 . The equal channel angular extrusion system of  claim 1 , wherein the material is piping, bar, tubing, plate, or hollow plate. 
     
     
         10 . The equal channel angular extrusion system of  claim 1 , wherein the shear zone is between 1 percent and 10 percent of the diameter of the material. 
     
     
         11 . The equal channel angular extrusion system of  claim 1 , wherein the pressure application device is a hydraulic ram or a piston. 
     
     
         12 . The equal channel angular extrusion system of  claim 1 , wherein the lubricant is a liquid lubricant, a dry lubricant, or combinations thereof. 
     
     
         13 . The equal channel angular extrusion system of  claim 12 , wherein the lubricant is an oil-based lubricant. 
     
     
         14 . The equal channel angular extrusion system of  claim 13 , wherein the lubricant is a petroleum fraction, a vegetable oil, a synthetic liquid, or combinations thereof. 
     
     
         15 . The equal channel angular extrusion system of  claim 14 , wherein the synthetic liquid is a silicone, a fluorocarbon, or combinations thereof. 
     
     
         16 . The equal channel angular extrusion system of  claim 12 , wherein the lubricant is graphite, a disulfide, or combinations thereof. 
     
     
         17 . The equal channel angular extrusion system of  claim 16 , wherein the disulfide is a tungsten disulfide, molybdenum, or combinations thereof. 
     
     
         18 . The equal channel angular extrusion system of  claim 1 , wherein the lubricant is applied to the exterior surface of the material by spraying, dipping, brushing, or combinations thereof. 
     
     
         19 . The equal channel angular extrusion system of  claim 1 , wherein the material is heated before the lubricant is applied to the exterior surface of the material. 
     
     
         20 . The equal channel angular extrusion system of  claim 1 , wherein the material is heated after the lubricant is applied to the exterior surface of the material.