Effect of Deformation Structure on Strength of a Low Alloyed Cu-Cr-Zr Alloy

Abstract:

The microstructure evolution and strength properties of a Cu-0.096%Cr-0.057%Zr alloy subjected to equal channel angular pressing (ECAP) at a temperature of 673 K via route B_C to total strains of 1 to 4 were examined. The planar low-angle boundaries with moderate misorientations form within initial grains during the first ECAP passes. Upon further processing the misorientations of these boundaries progressively increase and the formation of new ultrafine grains occurs as a result of continuous dynamic recrystallization. Partially recrystallized ultrafine grained structure evolves at strains above 4. After straining to 4 the (sub) grain size attains 0.65 μm. The large plastic straining provides significant strengthening. The ultimate tensile strength increases from 190 MPa in the initial state to 420 MPa after 4 ECAP passes. A modified Hall-Petch analysis is applied to investigate the contribution of grain refinement and dislocation density to the overall strengthening.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 1332-1337
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.1332
• Online since: November 2016
• Authors: A. Morozova*, Andrey Belyakov, Rustam Kaibyshev
• Keywords: Continuous Dynamic Recrystallization, Cu-Cr-Zr Alloy, Equal-Channel Angular Pressing (ECAP), Modified Hall-Petch Analysis, Strengthening

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