Effect of processing route and second phase particles on grain refinement during equal-channel angular extrusion

✍ Scribed by M. Berta; P.J. Apps; P.B. Prangnell

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 581 KB
• Volume: 410-411
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.08.026

✦ Synopsis

The effect of coarse and fine second-phase particles on the formation of ultra-fine grained (UFG) structures have been compared during severe deformation by equal-channel angular extrusion using routes A (no rotation) and B C (+90 • rotation). The presence of coarse particles has been found to increase the rate of grain refinement with route A and the homogeneity of the submicron grain structure formed, but appears less effective using route B C . In contrast, the presence of fine dispersoids inhibits the development of new high-angle grain boundaries and the formation of an UFG structure with both routes. Retardation is far more pronounced with rotation of the sample and the dispersiod-containing alloy processed by route B C contained mainly subgrains. The mechanisms operating in each case are discussed.