A study on the mechanical properties of cryorolled Al–Mg–Si alloy
15 May 2008-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing (Elsevier)-Vol. 480, Iss: 1, pp 299-305
TL;DR: In this article, the mechanical properties of a precipitation hardenable Al-Mg-Si alloy subjected to cryorolling and ageing treatments are reported in a solid solutionised state.
Abstract: The mechanical properties of a precipitation hardenable Al–Mg–Si alloy subjected to cryorolling and ageing treatments are reported in this present work. The severe strain induced during cryorolling of Al–Mg–Si alloys in the solid solutionised state produces ultrafine microstructures with improved mechanical properties such as strength and hardness. The improved strength and hardness of cryorolled alloys are due to the grain size effect and higher dislocation density. The ageing treatment of cryorolled Al–Mg–Si alloys has improved its strength and ductility significantly due to the precipitation hardening and grain coarsening mechanisms, respectively. The reduction in dimple size of cryorolled Al–Mg–Si alloy upon failure confirms the grain refinement and strain hardening mechanism operating in the severely deformed samples.
Citations
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TL;DR: In this article, a high-resolution electron backscatter diffraction technique was applied to quantify grain-structure development and texture evolution during/after cryogenic rolling of pure copper.
118 citations
01 Apr 2010
TL;DR: In this paper, a high-resolution electron-back-scatter-diffraction (EBSD) technique was applied to quantify grain-structure development and texture evolution during/after cryogenic rolling of pure copper.
Abstract: : A high-resolution electron-back-scatter-diffraction (EBSD) technique was applied to quantify grain-structure development and texture evolution during/after cryogenic rolling of pure copper. Microstructure evolution was found to be a complex process involving mainly geometrical effects associated with strain and discontinuous recrystallization but also including limited twinning and grain subdivision. Recrystallization was deduced to be static in nature and probably occurred during static storage of the material at room temperature after cryogenic rolling. The texture contained a pronounced {110} brass component; this observation was interpreted in terms of the suppression of cross slip at cryogenic temperatures. In general, cryogenic rolling was found to be ineffective for the formation of a nanocrystalline (NC) structure in pure copper.
112 citations
Cites background from "A study on the mechanical propertie..."
...This approach, known as “cryogenic deformation”, has recently been proposed as a means of producing bulk NC materials [4-10]....
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25 Sep 2008-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the effect of rolling temperature on its mechanical properties and microstructural characteristics by using tensile tests and SEM/electron back scattered diffraction, transmission electron microscope (TEM), DSC, X-ray diffraction (XRD) was studied.
Abstract: Aluminium alloy (6063) was severely rolled upto 92% thickness reduction at liquid nitrogen temperature and room temperature to study the effect of rolling temperature on its mechanical properties and microstructural characteristics by using tensile tests and SEM/electron back scattered diffraction (EBSD), transmission electron microscope (TEM), DSC, X-ray diffraction (XRD) as compared to room temperature rolled (RTR) material with the same deformation strain. An improved strength (257 MPa) of cryorolled 6063 Al alloy was observed as compared to the room temperature rolled alloy (232 MPa). The improved strength of cryorolled alloy is due to the accumulation of higher dislocation density than the room temperature rolled material. The tensile properties of cryorolled alloy and the alloy subjected to different annealing treatments were measured. The cryorolled alloy subjected to annealing treatment at 300 °C for 5 min exhibits an ultrafine-grained (UFG) microstructure with improved tensile strength and ductility.
91 citations
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TL;DR: In this article, the effect of plastic deformation on mechanical and ageing characteristics of Al-Mg-Si alloy (Al 6063 alloy) subjected to cryogenic and room temperature rolling was investigated by employing hardness measurements, tensile tests, XRD analysis, EBSD and TEM characterizations.
90 citations
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TL;DR: In this article, an aluminum-magnesium (Al 5083) alloy was subjected to cryorolling and warm rolling followed by warm rolling in order to investigate the changes in mechanical behavior and microstructure evolution.
77 citations
References
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TL;DR: In this paper, an attempt is made to explain the observed phenomena in the yielding and ageing of mild steel, described in two previous papers, in the general terms of a grain-boundary theory.
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