Effects of ECAE process on the fatigue crack growth rate of copper metal
- 6 January 2022
- journal article
- research article
- Published by SAGE Publications in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering
- Vol. 236 (4), 1536-1543
- https://doi.org/10.1177/09544089211067082
Abstract
In this study, the effects of the number of passes performed by the Equal Channel Angular Extrusion as a severe plastic deformation process on copper metal's microstructure and mechanical properties, especially its resistance to fatigue crack growth, have been investigated. The experimental results show that as the number of processes passes increases, the copper metal grains become finer and as a result less stress is concentrated at the starting points of the fatigue fracture, which delays the fracture. For example, after performing 8 ECAE process passes, the threshold values of fatigue crack growth increases by 113.2% relative to the base metal. Moreover, as the grains become smaller, the number of grains and consequently the number of grain boundaries will increase and thus more obstacles will be placed in the way of crack growth. Also, the SEM images indicate that many fine and equiaxed dimples in processed copper become smaller as the number of passes increases. This shows that finer and more equiaxed grains will be obtained by repeating the ECAE process and thus repeating the occurrence of recrystallization. It was cleared that this process improves the mechanical properties of the copper other than the failure strain. However, by increasing the number of process passes, this problem can be significantly reduced. HighlightsKeywords
This publication has 18 references indexed in Scilit:
- Grain growth in ultrafine grain sized copper during cyclic deformationJournal of Alloys and Compounds, 2014
- High-cycle fatigue strength and small-crack growth behavior of ultrafine-grained copper with post-ECAP annealingEngineering Fracture Mechanics, 2013
- Assessment of fatigue life and crack growth resistance of friction stir welded AISI 409M ferritic stainless steel jointsMaterials Science and Engineering: A, 2012
- Fracture toughness and fatigue crack growth characteristics of nanotwinned copperActa Materialia, 2011
- Fatigue crack growth resistance of ECAPed ultrafine-grained copperEngineering Fracture Mechanics, 2010
- Fatigue crack growth in ECAPed commercially pure UFG copperProcedia Engineering, 2010
- Effect of stress ratio on the fatigue behavior of a friction stir processed cast Al–Si–Mg alloyScripta Materialia, 2009
- Fatigue behavior and damage characteristic of ultra-fine grain low-purity copper processed by equal-channel angular pressing (ECAP)Materials Science and Engineering: A, 2008
- Fatigue limit and crack growth in ultra-fine grain metals produced by severe plastic deformationJournal of Materials Science, 2006
- Fatigue crack growth behavior in Sn–Pb eutectic solder/copper joint under mode I loadingMechanics of Materials, 2005