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Roohollah Jamaati - One of the best experts on this subject based on the ideXlab platform.
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Nanostructured AA5005/Al2O3 composite manufactured by anodising and Accumulative Roll bonding
Materials Science and Technology, 2018Co-Authors: Roohollah JamaatiAbstract:In this study, nanostructured AA5005/6 vol.-% Al2O3 composite manufactured by anodising and Accumulative Roll bonding (ARB) processes was investigated. The microstructure of the AA5005/Al2O3 compos...
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Fracture of steel nanocomposite made using Accumulative Roll bonding
Materials Science and Technology, 2014Co-Authors: Roohollah Jamaati, Mohammad Reza Toroghinejad, Hossein Edris, Mohammad Reza SalmaniAbstract:AbstractIn this study, the fracture behaviour of steel based composite and nanocomposite fabricated by Accumulative Roll bonding process was investigated using scanning electron microscopy fractography. The nanocomposite failed through decohesion and then void nucleation and linking in the matrix near the reinforcement/matrix interface and without particle fracture mechanism, whereas the composite failed through both decohesion and particle fracture mechanisms and then void nucleation, growth, and coalescence in the matrix near the reinforcement. The results indicated that the fracture mode after first cycle for pure interstitial steel, composite and nanocomposite is combination of ductile and shear ductile fracture. But, with increasing the number of cycles, the dimple size and the dimple depth decreased.
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on the use of Accumulative Roll bonding process to develop nanostructured aluminum alloy 5083
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2013Co-Authors: Mohammad Reza Toroghinejad, Roohollah Jamaati, Fakhreddin AshrafizadehAbstract:Abstract In the present study, the effect of Accumulative Roll bonding (ARB) process at room temperature on the microstructure and mechanical properties of AA5083 strip was investigated. Microstructural observations were done by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Also, mechanical properties were performed by tensile, hardness, and microhardness tests. It was observed that Accumulative Roll bonding is a promising process for production of nanostructured (80 nm) AA5083 strips. Nano shear bands were formed in the microstructure after the fourth cycles. When the number of cycles increased, the tensile strength and hardness of the Accumulatively Roll bonded strips increased. However, by increasing the number of cycles, the elongation value decreased except for the last (sixth) cycle. It was found that when the number of cycles increased, the distribution of microhardness values became more uniform. After the tensile test, debonding can be observed especially in the interface formed in the last cycle. Observations revealed that the failure mode in the Accumulatively Roll bonded AA5083 strip was a shear ductile rupture with elongated shallow shear dimples.
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Investigation of nanostructured Al/Al2O3 composite produced by Accumulative Roll bonding process
Materials and Design, 2012Co-Authors: Roohollah Jamaati, Mohammad Reza Toroghinejad, Jan DutkiewiczAbstract:In this study, the Accumulative Roll bonding (ARB) process was used for manufacturing nanostructured aluminum/15. vol.% alumina composites. Microstructural characterization by transmission electron microscopy (TEM) identified the severe shear deformation, however, the grain growth was restrained by particles of oxide film and recrystallization produced the nanograins with an average size
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high strength and highly uniform composite produced by anodizing and Accumulative Roll bonding processes
Materials & Design, 2010Co-Authors: Roohollah Jamaati, Mohammad Reza ToroghinejadAbstract:Abstract The anodizing and Accumulative Roll bonding (ARB) processes are used in this paper as a new, effective alternative for manufacturing high-strength and highly-uniform aluminum/alumina composites. Four different thicknesses of alumina layers are grown on the substrate using an anodizing process and the microstructural evolution and mechanical properties of the resulting aluminum/alumina composite are investigated. Microscopic investigations of the composite show a uniform distribution of alumina particles in the matrix. It is found that alumina layers produced by the anodizing process neck, fracture, and depart as the number of Accumulative Roll bonding passes increases. During ARB, it is observed that as strain increases with the number of passes, the strength and elongation of the produced composites correspondingly increase. Also, by increasing alumina quantity, tensile strength improves so that the tensile strength of the Al/3.55 vol.% Al2O3 composite becomes ∼3.5 times greater than that of the annealed aluminum used as raw material.
Nobuhiro Tsuji - One of the best experts on this subject based on the ideXlab platform.
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Development of highly cube textured nickel superconductor substrate tapes by Accumulative Roll Bonding (ARB)
International Journal of Materials Research, 2011Co-Authors: Pinaki Prasad Bhattacharjee, Nobuhiro TsujiAbstract:Development of cube texture ({001}〈100〉) has been investigated in pure Ni (99.97 %) deformed to ultrahigh straining (e = 6.4) by Accumulative Roll bonding and then annealed at different temperatures for use as coated superconductor substrate. The as Accumulative Roll bonding processed sheets reveal a typical pure metal or copper type homogeneous deformation texture. After annealing at different temperatures, strong cube texture formation is observed and a nearly 100% cube textured tape with almost twin-free microstructure is obtained after annealing at 800 °C for 1 h. The development of a sharp cube texture is accompanied by the development of a predominantly low angle boundary network. The very sharp cube texture formation in this material appears to be due to the oriented nucleation of cube grains at early stages of recrystallization and selective growth of these grains with progressing recrystallization. The results obtained indicate that Accumulative Roll bonding could be a very attractive route for fabricating highly cube textured superconductor substrate tapes from Ni.
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Friction stir welding of ultrafine grained Al alloy 1100 produced by Accumulative Roll-bonding
Scripta Materialia, 2003Co-Authors: Yutaka S. Sato, Y. Kurihara, Hiroyuki Kokawa, Seung Hwan C. Park, Nobuhiro TsujiAbstract:Abstract Friction stir welding (FSW) was applied to an Accumulative Roll-bonded (ARBed) Al alloy 1100. FSW resulted in reproduction of fine grains in the stir zone and small growth of the ultrafine grains of the ARBed material just outside the stir zone. Consequently, FSW effectively prevented the softening in the ARBed alloy.
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microstructural evolution during Accumulative Roll bonding of commercial purity aluminum
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2003Co-Authors: Xiaoxu Huang, Nobuhiro Tsuji, N Hansen, Yoritoshi MinaminoAbstract:The microstructure in commercial purity aluminum deformed from medium to high strain (evM=1.6–6.4) by Accumulative Roll-bonding (ARB) at 473 K was quantitatively examined by transmission electron microscopy. It was found that a sub-micrometer lamellar structure characterizes the microstructure at high strains (evM>1.6), and that the lamellar boundary spacing decreases and the misorientation across the lamellar boundaries increases with increasing Rolling strain. This characteristic evolution has also been observed during conventional cold-Rolling of commercial purity aluminum. However, a comparison between the two processes shows a significant difference in the evolution of the microstructural parameters. These differences are discussed based on the different processing conditions characterizing ARB and conventional Rolling, respectively.
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role of shear strain in ultragrain refinement by Accumulative Roll bonding arb process
Scripta Materialia, 2002Co-Authors: Yoshihiko Saito, Hiroshi Utsunomiya, Nobuhiro Tsuji, Tetsuo SakaiAbstract:Abstract The role of shear strain on ultragrain refinement of aluminum during Accumulative Roll-bonding (ARB) process was studied. The complicated distribution of redundant shear strain through thickness of the ARB processed sheets was quantitatively shown first, and good correspondence between the grain size and the amount of shear strain was found.
Heinz Werner Höppel - One of the best experts on this subject based on the ideXlab platform.
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A multiscale simulation framework of the Accumulative Roll bonding process accounting for texture evolution
Materials Science and Engineering: A, 2015Co-Authors: Aruna Prakash, Heinz Werner Höppel, Wolfram Georg Nöhring, Ricardo A. Lebensohn, Erik BitzekAbstract:The Accumulative Roll bonding process is one of the most prominent severe plastic deformation processes for obtaining sheet materials with ultra-fine-grained microstructures and high strength. The properties of such sheets differ significantly from those of conventionally Rolled sheets. It is hence desirable to have a simulation framework that can accurately predict the material properties, including the evolving texture and anisotropy during processing. Here, we propose such a framework for multiple pass Rolling using explicit finite elements and embedding the visco-plastic self-consistent (VPSC) polycrystal texture model for the material response. To facilitate multiple pass Rolling, we propose a novel solution mapping scheme that transfers the material state from the deformed finite element mesh to a new one. Additionally, we implement a two-level parallelization scheme – with decomposition of the FE domain using message passing interface (MPI) and thread based parallelization of the material response using openMP – to ensure reduced simulation times. The predictive capabilities of the proposed framework are demonstrated by simulating the Accumulative Roll bonding of aluminum alloy AA5754 sheets. The simulations validate the working of the solution mapping scheme, and clearly show the development of a through thickness gradient of texture and anisotropy in the Roll-bonded sheet after two passes.
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Influence of upscaling Accumulative Roll bonding on the homogeneity and mechanical properties of AA1050A
Journal of Materials Science, 2013Co-Authors: M. Ruppert, Heinz Werner Höppel, W. Böhm, H. Nguyen, M. Merklein, Mathias GökenAbstract:Accumulative Roll bonding (ARB), as a method for production of ultrafine grained materials, is frequently supposed to be easily transferable to established industrial production lines. In literature, however, common sheet dimensions used for ARB in a laboratory scale are between 20 and 100 mm in width. In order to quantify the potential of upscaling the ARB process to a technological relevant level, sheets of AA1050A with an initial sheet width of 100–450 mm were Accumulative Roll bonded up to 8 cycles. In this regard, three different Rolling mills of distinct dimensions were used for processing of the sheet material. The influence of process parameters and the reproducibility of the process, in terms of mechanical properties and homogeneity of the sheets, were studied by means of mechanical and microstructural characterization. Both appear to be largely independent on the sheet size and the Rolling mill utilized for production. Only small deviations after the first cycles could be detected, vanishing in subsequent cycles due to the features of microstructural evolution. The finally obtained results indicate a high potential for industrial application of ARB and illustrate the possibility to upscale the process to a level necessary for that purpose.
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Mechanical properties of aluminium laminates produced by Accumulative Roll bonding: Mechanical properties of aluminium laminates produced by Accumulative Roll bonding
Crystal Research and Technology, 2013Co-Authors: Paul Chekhonin, Tina Hausöl, Heinz Werner Höppel, Juliane Scharnweber, M. Scharnweber, Carl-georg Oertel, J. Jaschinski, T. Marr, Werner SkrotzkiAbstract:Laminates of high and commercial purity aluminium layers were processed by Accumulative Roll bonding performed up to ten cycles. The mechanical properties were measured by tensile testing. Both yield strength and ultimate tensile strength increase with higher number of cycles. The fracture strain is decreased through the first ARB cycle, but increases during further processing to reach a maximum after the sixth cycle. It is found that the development of the microstructure, especially in the high purity layers, strongly influences the mechanical properties.
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Tailored Heat Treated Accumulative Roll Bonded Aluminum Blanks: Microstructure and Mechanical Behavior
Metallurgical and Materials Transactions A, 2012Co-Authors: Verena Maier, Tina Hausöl, Christian W. Schmidt, Heinz Werner Höppel, Wolfgang Böhm, Hung Nguyen, Marion Merklein, Mathias GökenAbstract:Aluminum alloy AA6016 was Accumulative Roll bonded up to eight cycles and investigated regarding formability by bending tests. Due to the limited bendability of Accumulative Roll bonding (ARB) processed materials, a tailored laser heat treatment was performed along the bending edge before forming. This tailored laser heat treatment causes a local recrystallization and recovery of the bending samples at the deformation zone, which locally increases ductility and allows higher bending angles achievable with lower forming forces. Between the recrystallized heat treated zone and the unaffected ultrafine-grained (UFG) base material, a gradient in grain size with a bimodal region is formed. This observed microstructural profile is confirmed by local mechanical testing measuring the hardness and strain rate sensitivity by nanoindentation techniques.
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particle based alloying by Accumulative Roll bonding in the system al cu
Metals, 2011Co-Authors: Christian W. Schmidt, Heinz Werner Höppel, Patrick Knodler, Mathias GökenAbstract:Abstract: The formation of alloys by particle reinforcement during Accumulative Roll bonding (ARB), and subsequent annealing, is introduced on the basis of the binary alloy system Al-Cu, where strength and electrical conductivity are examined in different microstructural states. An ultimate tensile strength (UTS) of 430 MPa for Al with 1.4 vol.% Cu was reached after three ARB cycles, which almost equals UTS of the commercially available Al-Cu alloy AA2017A with a similar copper content. Regarding electrical conductivity, the UFG structure had no significant influence. Alloying of aluminum with copper leads to a linear decrease in conductivity of 0.78 µΩ·cm/at.% following the Nordheim rule. On the copper-rich side, alloying with aluminum leads to a slight strengthening, but drastically reduces conductivity. A linear decrease of electrical conductivity of 1.19 µΩ·cm/at.% was obtained. Keywords: Accumulative Roll bonding (ARB); particle reinforcement; ultrafine-grained microstructure; alloying; strength; electrical conductivity
Oscar Antonio Ruano - One of the best experts on this subject based on the ideXlab platform.
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Bond Strength of Ultrafine Grained Zr Fabricated by Accumulative Roll Bonding
Materials Science Forum, 2008Co-Authors: Ling Jiang, Oscar Antonio Ruano, Maria Teresa Pérez-prado, Michael E. KassnerAbstract:The bond strength of ultrafine grained Zr with a grain size of 0.4 µm, fabricated by Accumulative Roll bonding (ARB), was assessed. The shear strength of the bond was estimated to be about 20% of the shear fracture strength of the as processed metal, a ratio significantly higher than that found in other materials processed by similar methods. The favorable degree of bonding achieved is attributed to the high ductility of Zr as well as to the high reductions used during the ARB process.
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The fabrication of bulk ultrafine-grained zirconium by Accumulative Roll bonding
JOM, 2007Co-Authors: Ling Jiang, Oscar Antonio Ruano, Michael E. Kassner, Maria Teresa Pérez-pradoAbstract:This work demonstrates that bulk ultrafine-grained zirconium can be fabricated by Accumulative Roll bonding. Grain refinement takes place by geometrical thinning and grain subdivision through the formation of geometrically necessary boundaries. This is consistent with the stabilization of a typical Rolling texture during processing and with the absence of any recrystallization texture components. The ultrafine-grained zirconium possesses high ultimate tensile strength, good ductility, and a remarkable strain hardening capacity.
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Accumulative Roll bonding of a Mg-based AZ61 alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2005Co-Authors: J A Del Valle, Maria Teresa Pérez-prado, Oscar Antonio RuanoAbstract:Abstract This work aims to investigate whether Accumulative Roll bonding (ARB) is an effective grain refinement technique for the Mg–Al alloy AZ61. Thus, a number of ARB routes at 300 °C and 400 °C, using thickness reductions per pass of 25%, 50%, 66%, and 80%, were performed. It was found that both the ultimate grain size achieved, as well as the degree of bonding, depend on the Rolling temperature and on the thickness reduction per pass. Higher temperatures and higher reductions promote a larger degree of bonding. Increasing strain also favors the formation of a more homogeneous microstructure. The smallest grain sizes were obtained at the lowest Rolling temperature.
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grain refinement of mg al zn alloys via Accumulative Roll bonding
Scripta Materialia, 2004Co-Authors: M T Perezprado, J A Del Valle, Oscar Antonio RuanoAbstract:Abstract An increase in the Al content of Mg AZ alloys from 3% to 9% allows obtaining ultra-fine grain sizes via severe plastic deformation by Accumulative Roll bonding. The final grain size is reached after the first pass. However, the homogeneity of the processed microstructure increases with the number of passes.
John G. Lenard - One of the best experts on this subject based on the ideXlab platform.
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Severe Plastic Deformation — Accumulative Roll Bonding
Primer on Flat Rolling, 2014Co-Authors: John G. LenardAbstract:The interest in bulk nanostructured materials, processed by the methods of severe plastic deformation, is justified by the unique physical and mechanical properties of the resulting products. The advantage of these over other processes is related to overcoming the difficulties connected to residual porosity in compacted samples, impurities from ball milling, processing of large-scale billets, and the practical application of the resulting materials. The methods of severe plastic deformation create ultrafine-grained structures with prevailing high-angle grain boundaries. They should also be able to create uniform nanostructures within the whole volume of a sample to provide stable properties of the processed materials, and they should not suffer mechanical damage when exposed to large plastic deformations. This chapter presents a discussion of processes that apply severe plastic deformation to create small grains, thereby increase their strength. It describes the method of Accumulative Roll bonding. This chapter discusses this mehtod, followed by a detailed discussion of a set of experiments related to it. It also discusses the potential industrial application of the Accumulative Roll bonding process and the creation of tailor-Rolled blanks.
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Chapter 8 – Severe Plastic Deformation — Accumulative Roll Bonding
Primer on Flat Rolling, 2007Co-Authors: John G. LenardAbstract:Publisher Summary The interest in bulk nanostructured materials, processed by the methods of severe plastic deformation, is justified by the unique physical and mechanical properties of the resulting products. The advantage of these over other processes is related to overcoming the difficulties connected to residual porosity in compacted samples, impurities from ball milling, processing of large-scale billets, and the practical application of the resulting materials. The methods of severe plastic deformation create ultrafine-grained structures with prevailing high-angle grain boundaries. They should also be able to create uniform nanostructures within the whole volume of a sample to provide stable properties of the processed materials, and they should not suffer mechanical damage when exposed to large plastic deformations. This chapter presents a discussion of processes that apply severe plastic deformation to create small grains, thereby increase their strength. It describes the method of Accumulative Roll bonding. This chapter discusses this mehtod, followed by a detailed discussion of a set of experiments related to it. It also discusses the potential industrial application of the Accumulative Roll bonding process and the creation of tailor-Rolled blanks.
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An examination of the Accumulative Roll-bonding process
Journal of Materials Processing Technology, 2004Co-Authors: György Krállics, John G. LenardAbstract:Abstract Ultra-low-carbon steel strips containing 0.002% C were Rolled at 500 °C, following the steps of the Accumulative Roll-bonding process. Strips of 32 layers were created. The mechanical attributes after Rolling and cooling were examined and the development of edge cracking was monitored. The metal’s yield and tensile strengths increased by 200–300% while the ductility dropped from a pre-Rolled value of 75 to 4%. The Rolling process was stopped when cracking of the edges became pronounced. The shear strength of the bond was about 60% of the yield strength in shear. The accumulation of the retained strain after dynamic recovery caused cracking at the edges. A potential industrial application of the Accumulative Roll-bonding process, that of the creation of tailored blanks, is discussed.