Effects of Initial Microstructure and Deformation Method on Grain Refinement in a Cu-Cr-Zr Alloy

Abstract:

The development of submicrocrystalline structure in a Cu-0.3wt.%Cr-0.5wt.%Zr during multidirectional forging (MDF) and equal channel angular pressing (ECAP) was investigated in comparison. A large number of strain-induced subboundaries with low-angle misorientations appeared at early deformation. The subsequent straining led to an increase in the misorientations of these subboundaries, resulting in the formation of submicrocrystalline structure at sufficiently large strains. The process of microstructural evolution can be considered as continuous dynamic recrystallization. MDF provided faster kinetics of new ultrafine grain formation as compared to ECAP. The fraction of ultrafine grains with a size below 2 μm comprised 0.59 or 0.23 after MDF or ECAP to a total strain of 4, respectively. The grain refinement kinetics could be accelerated by the presence of second phase precipitates. The fraction of ultrafine grains after MDF to a strain of 4 achieved 0.36 or 0.59 in the solution treated or aged samples, respectively.

• Periodical: Materials Science Forum (Volumes 838-839)
• Pages: 308-313
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.838-839.308
• Online since: January 2016
• Authors: Iaroslava Shakhova*, Andrey Belyakov, Rustam Kaibyshev
• Keywords: Cu-Cr-Zr Alloy, Dynamic Recrystallization, ECAP, Multidirectional Forging, Ultra-Fine Grained Structure

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