Developing a Model for Grain Refinement in Equal-Channel Angular Pressing

Abstract:

It is now recognized that processing by equal-channel angular pressing (ECAP) leads to very significant grain refinement in polycrystalline materials with the as-pressed grains typically having sizes within the submicrometer range. Furthermore, the materials produced by ECAP exhibit many useful properties including a high strength at ambient temperatures and, if these ultrafine grains are retained to elevated temperatures, a potential for superplastic forming. This paper examines the fundamental characteristics of grain refinement by making use of two sets of experimental observations: experimental data obtained from the pressing of aluminum single crystals through one pass of ECAP and hardness measurements taken on polycrystalline aluminum for samples subjected to ECAP for up to a total of eight passes. These experimental results are used to develop a microstructural model that provides a satisfactory explanation for the grain refinement occurring in ECAP.

• Periodical: Materials Science Forum (Volumes 503-504)
• Pages: 19-24
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.503-504.19
• Online since: January 2006
• Authors: Cheng Xu, Minoru Furukawa, Z. Horita, Terence G. Langdon
• Keywords: Aluminum (Al), Equal-Channel Angular Pressing (ECAP), Grain Refinement, Homogeneity, Microhardness

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