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accumulative-roll-bonded
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Characterization of nanostructured aluminum sheets processed by accumulative roll bonding
, Article International Journal of Modern Physics B ; Volume 22, Issue 18-19 , 2008 , Pages 2840-2847 ; 02179792 (ISSN) ; Akbarzadeh, A ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2008
Abstract
An ultrafine grained (UFG) aluminum sheet was produced using severe plastic deformation (SPD) by a process known as accumulative roll bonding (ARB). Electron Back Scattered Diffraction (EBSD) method and Transmission Electron Microscopy (TEM) were utilized for characterization of the subgrain and grain structures of the processed sheets. The results indicate that different mechanisms at different levels of strain lead to the gradual evolution of ultrafine or nanocrystalline grains. Grain fragmentation as well as the development of subgrains are the major mechanisms at the early stages of ARB. Strain induced transformation of low angle to high angle grain boundaries and formation of a thin...
Structural and Microstructural Study on Al/Ti Intermetallic Sheets Produced by ARB
, M.Sc. Thesis Sharif University of Technology ; Ekrami, Ali Akbar (Supervisor) ; Akbarzadeh, Abbas (Supervisor)
Abstract
Due to special physical and mechanical properties of intermetallic compounds,somehow in between of the metallic and ceramic extremes, their applications are increased in different industries. Among these materials, titanium aluminides due to their low density, high specific strength and excellent corrosion and oxidation resistance has got more attention. Because of similar high temperature properties and lower density, these compounds are suitable alternatives for nickel base superalloys. Accumulative Roll Bonding (ARB) of pure metallic sheets and the following heat treatment in production of intermetallic compounds can be considered as a manufacturing process. The goal of this study is...
Deposition of Ceramic Nanoparticles on Aluminum Sheet by Air Gun Spraying for ARB Processing of Nanocomposite Sheets
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor)
Abstract
Particle reinforced aluminum matrix composites have considerable attraction in automotive and aerospace industries due to their special properties as light weight, high ratio of strength/density, improved elastic modulus, low coefficient of thermal expansion and high wear and corrosion resistance. Among the production processes of metal matrix composites, accumulative roll bonding process has particular importance due to producing ultrafine grained composite sheets. However, uncontrolled and undesired agglomeration of particles is the main problem in producing these composites. In this research, the Al2O3 and SiC nanoparticles were electrostatically stabilized against agglomeration by...
Production and Characterization of AA5083 Aluminium Sandwich Sheet with Porous (FOAM) Core by Accumulative Roll Bonding
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor)
Abstract
In this research, aluminium sandwich structure was manufactured by accumulative roll bonding (ARB). In this method, aluminum AA5083 strip was used as the matrix and titanium hydride was selected as the foaming agent powder. Due to the use of particle foaming agent in the first pass, reduction, preheat temperature, rolling speed and the percentage of powder particles parameters were examined. Finally, the 66% reduction, 400 °C preheat temperature and 25 rpm rolling speed, were considered as the optimal values. At the next stage of this process 50% reduction was applied at each pass and this process was repeated up to five passes. After ward, in order to create a sandwich structure, aluminum...
Role of second phase particles on microstructure and texture evolution of ARB processed aluminium sheets
, Article Materials Science and Technology ; Volume 25, Issue 5 , 2009 , Pages 625-631 ; 02670836 (ISSN) ; Akbarzadeh, A ; Sharif University of Technology
2009
Abstract
The accumulative roll bonding (ARB) process was carried out on a high purity alloy (AA1100) and a particle containing aluminium alloy (AA3003) for up to eight cycles. The electron backscattered diffraction (EBSD) method was utilised to investigate the microstructural and microtextural evolution in ARB processed sheets. The results indicate that the lack of second phase particles in pure aluminium hinders grain refinement and leads to the formation of unrefined bands, which results in the increase of the overall texture intensity and the development of a strong texture. Asubmicrometre grain structure in this alloy develops at the final stages of the process. It was also found that the...
Flow stress analysis of ultrafine grained AA 1050 by plane strain compression test
, Article Materials Science and Engineering A ; Vol. 593 , 2014 , pp. 136-144 ; ISSN: 09215093 ; Akbarzadeh, A ; Yoon, Y. O ; Kim, S. K ; Sharif University of Technology
Abstract
Plane strain compression (PSC) test was used to study the flow stress of ultrafine grained commercially pure aluminum at large strains. AA 1050 sheets were processed by various Accumulative Roll-Bonding (ARB) cycles up to 10 cycles as the initial specimens for the test. An approach was developed to measure the coefficient of friction and to suppress its effect on the results. It is shown that as a result of having an anisotropy parameter (R-value) of less than one, Von-Mises tensile strengths are significantly higher than PSC strengths. Comparing these strengths, the R-value as an average anisotropy parameter of rolling and transverse directions is estimated for the ARBed sheets, where it is...
Fabrication of aluminium matrix composites reinforced by submicrometre and nanosize Al 2O 3 via accumulative roll bonding
, Article Materials Science and Technology (United Kingdom) ; 2012 , Pages 1233-1240 ; 02670836 (ISSN) ; Akbarzadeh, A ; Sharif University of Technology
2012
Abstract
Aluminium matrix composites reinforced with submicrometre and nanosize Al 2O 3 particles were successfully manufactured in the form of sheets through eight cycles of accumulative roll bonding process. The mechanical properties of the produced composite are compared with accumulative roll bonded commercially pure aluminium. It is shown that only 1 vol.-% of submicrometre or nanosize alumina particles as reinforcement in the structure can significantly improve the yield and ultimate tensile strengths. Scanning electron microscopy revealed that particles have a random and uniform distribution in the matrix especially in the less volume fraction of alumina particles, and strong mechanical...
Using ARB Process for Metal Matrix Foam and Composite Production
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor)
Abstract
Metal matrix composites (MMC) and metal foams (MF) have been the topic of numerous researches during the last decades. The appropriate mechanical and physical properties of these materials make them useful in various industries. In this research, a unique approach is introduced for producing MMCs and MFs in which accumulative roll bonding (ARB) is employed in order to achieve a homogeneous distribution of ceramic particles in the metal matrix. Also, foamed structures can be made by subjecting Al/TiH2 composite to an appropriate annealing heat treatment where TiH2 particles decompose to hydrogen and titanium. In this work, the effect of number of ARB cycles on the size and distribution of...
Investigation of Structure, Microstructure and Mechanical Properties of Al/AZ31 Composite Produced by ARB
,
M.Sc. Thesis
Sharif University of Technology
;
Akbarzadeh Changiz, Abbas
(Supervisor)
Abstract
Metallic multilayer composites provide remarkable mechanical, electrical and magnetic properties. These kinds of composites are recently processed by severe plastic deformation methods. Accumulative roll bonding (ARB) is one of the SPD processes in which accumulation of strain by repeating cycles, leads to the ultra fine grains structures. The goal of this research is manufacturing of Al/AZ31 composite and investigating the relation between the rolling process parameters and the mechanical and physical properties of the final sheet. The initial composite was carried out by cladding of 1mm thick AZ31 sheet in between two commercially pure aluminum sheets with the same thickness (57%...
Design, Fabrication and Characterization of Lead-Free Nano-Composite Solder Sn-Ag-Cu/ CeO2
, Ph.D. Dissertation Sharif University of Technology ; Kokabi, Amir Hossein (Supervisor) ; Madaah Hosseini, Hamid Reza (Supervisor)
Abstract
As one of the key technologies for high performance electronic devices, composite solders have been recently developed to improve thermal and mechanical properties of solder joints. In this study, accumulative roll bonding (ARB) process was used as an effective alternative method for manufacturing high-strength, finely dispersed, void-free and highly uniform Sn-Ag-Cu/CeO2 nanocomposite solders. Microstructural investigation of nanocomposite solders revealed that homogenous distribution of CeO2 nanoparticle has been achieved and the eutectic as-cast morphology of the solder changed to recrystallized fine grained structure. As a result of severe plastic deformation during rolling, brittle and...
Evaluation of Bonding and Mechanical Properties of Metal-Polymer Sheets Manufactured by Roll Bonding
, Ph.D. Dissertation Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor) ; Kokabi, Amir Hossein (Co-Advisor)
Abstract
Emission of the greenhouse gases is a great concern and use of lightweight materials in transport vehicles has found a major importance in this respect. Metal/polymer laminated composites are of great interest due to their special mechanical properties and thoughness. Application of metal/polymer sheets is limited because of low bonding strength of metals and polymers in these sheets, which is not sufficient, to endure the stresses and strains during deformation processes such as deep drawing and bending. In this research, roll bonding of AA5052/Polypropylene sheets is investigated and the effects of bonding parameters on strength are evaluated and finally the bonding mechanisms during...
Finite Element Modeling of Particle Distribution in Al/Powder Composite Sheets Processed by ARB for Manufacturing Aluminium Foams
, M.Sc. Thesis Sharif University of Technology ; Akbarzade, Abbas (Supervisor)
Abstract
In this study closed cell aluminum foam was manufactured through accumulative roll bonding (ARB). In this method, aluminum AA1050 strip was used as the matrix and calcium carbonate was selected as blowing agent powder. The strips were roll-bonded with reduction of 50% during each pass. The produced composite was then subjected to different foaming conditions in order to achieve foams with maximum porosity. Subsequently, influences of content of the blowing agent, time, pressure, number of rolling passes and heating rate on the percentage of porosities were evaluated. In optimum condition quantity of the blowing agent, foaming temperature, holding time and number of ARB passes were equal to 1...
Physical Modeling of Metal Matrix Composite Sheets With Second Phase Manufactured by Accumulative Roll Bonding (ARB) of Al-Ni Laminations
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor)
Abstract
Metallic multilayer composites provide remarkable mechanical, electrical and magnetic properties. These kinds of composites have been recently processed by severe plastic deformation (SPD) methods. Accumulative roll bonding (ARB) is one of the SPD processes in which accumulation of strain by repeating cycles, leads to the ultra fine grained materials. The goal of this research is manufacturing of Al/Ni composite sheets by ARB process considering the effects of thickness and number of initial sheets on their mechanical properties and microstructures. The initial composites were produced by commercially pure Al and Ni as the matrix and the reinforcement, respectively. Thickness of the Al...
Processing Nano Composite Structure of 1100 and 3004 Al Alloy Sheets Using ARB Technique and Study Influence of Heat Treatment on the Grain Structure
, M.Sc. Thesis Sharif University of Technology ; Asgari, Sirous (Supervisor)
Abstract
At this study, nano structure sheet composite produced by1100 and 3004 strips using Accumulative role banding then mechanical and physical properties of the composites were investigated. After surface preparation, primary composite samples produced by putting different layers on each other and then rolling. The rolling was occurred in two steps; thickness reduction at first and second step were about 50% and 34%, respectively. ARB process were done till ninth cycle for Primary composite samples. To investigate mechanical properties of the samples, hardness, micro hardness and tensile strength tests have been done. Furthermore, micro structure of selective samples were studied by light...
Production of Nanostructured Composite Sheets of AA1100/St37 Using ARB Technique and Evaluation of Heat Treatment Effect on Grains Structure
, M.Sc. Thesis Sharif University of Technology ; Asgari, Sirous (Supervisor)
Abstract
In present work, nanostructured multilayer composites produced from AA1100 and St37 alloys and mechanical properties of resulted samples characterized using tension and micro hardness tests. Also dispersion pattern of second phase in matrix studied via optical microscopy. Thickness of second phase layers showed a little reduction after 2 ARB cycles; but their length decrease gradually. With increasing number of ARB cycles up to 6 cycles, sample's tensile strength first decrease rapidly and after that increased, but never reached initial value. In order to evaluation of heat treatment effects on samples grain structure, samples heat treated and tensile test carried on them. Annealing at 300...
Processing of Nanostructured Composite from Al1050 and Al2024 Via Aaccumulative Roll Bonding (ARB) and Study of Heattreatment Effects on its Microstructure and Mechanical Properties
, M.Sc. Thesis Sharif University of Technology ; Asgari, Sirous (Supervisor)
Abstract
In this study nanostructured composite from Al1050 and Al2024 were manufactured via accumulative roll bonding (ARB). Process was conducted in two different ways. In one approach the Al2024 sheets were annealed and in the other they were solution treated (ST). The sheets were degreased by acetone and wire-brushed, and then one Al2024 was placed between two sheets of Al1050, so three pieces of sheets were stacked to be 3 mm in thickness. The stacked sheets were rollbonded to produce the primary composite sandwich with thickness of 1 mm. Then, this sandwich was cut in the half and the two halves were degreased and wire-brushed and stacked to be 2 mm in thickness. Roll-bonding was conducted...
Ductility Enhancement of Accumulative Roll bonded Aluminum Sheet by Developing a Bimodal Grain Size Distribution
, M.Sc. Thesis Sharif University of Technology ; Seyyed Reyhani, Morteza (Supervisor) ; Akbarzadeh Changiz, Abbas (Supervisor)
Abstract
The goal of this project is production of composite laminated sheetswith bimodal microstructure using ARB process. It is planned to produce a laminated sheet having bimodal grain size distribution in microstructure to increase the formability while maintaining the strength. Two different aluminum alloys including AA 1050 and AA5083 were ARB processed up to 9 cycles, Then the ARB samples were annealed under controlled temperatures and times. Due to structural differences like stacking fault energy,stored cold work energy and solute atoms concentration, annealing ofThese two alloys lead to different recrystallized grain sizes. In order to evaluate the recovery and recrystallization behavior of...
Comparison of the Effect of Controlled Annealing on Accumulative Roll Bonded 5083 Aluminum Alloy and AZ31 Magnesium Alloy Sheets
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh, Abbas (Supervisor)
Abstract
Lightweight aluminum and magnesium alloy sheets do not generally possess as much strength as steel sheets and their strength need to be increased by a suitable process such as Accumulative Roll Bonding (ARB). One of the most important limitations of ARB is the low ductility and formability of the sheets produced by this process. In the present research conducted on the 5083 aluminum and AZ31 magnesium alloy sheets efforts have beem made to overcome this limitation by heating up the sheets whether during metal forming process as hot deformation or as distinct controlled annealing process subsequent to the deformation, in order to develop the application domain of the sheets. Results...
Investigation of the Effects of Various Parameters on Microstructure and Mechanical Properties of Nano-Composite Al-Al2O3 and Al-Sic Produced by Accumulative Roll Bonding
, M.Sc. Thesis Sharif University of Technology ; Akbarzadeh Changiz, Abbas (Supervisor)
Abstract
Accumulative roll bonding has been used as novel method to produce the composite with ultra fine grain microstructure. This method has two steps, impose the particles as reinforcement between the layers by roll bonding process and then distribute the particles in matrix and generat an ultra fine grain microstructure during the ARB passes. In the present work, ARB process was performed to produce the Al/SiC and Al/Al2O3 nano-composites with various particles size and different volume fraction of reinforcement. Microscopic observations such as OM, SEM and TEM and XRD analyses were used to investigate the microstructure of produced composites and the distribution of the particles in matrix...
Analysis of strain rate sensitivity of ultrafine-grained AA1050 by stress relaxation test
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 45, Issue 12 , November 2014 , Pages 5442-5450 ; Akbarzadeh, A ; Kim, B. H ; Kim, S. K ; Sharif University of Technology
Abstract
Commercially pure aluminum sheets, AA 1050, are processed by accumulative roll bonding (ARB) up to eight cycles to achieve ultrafine-grained (UFG) aluminum as primary material for mechanical testing. Optical microscopy and electron backscattering diffraction analysis are used for microstructural analysis of the processed sheets. Strain rate sensitivity (m-value) of the specimens is measured over a wide range of strain rates by stress relaxation test under plane strain compression. It is shown that the flow stress activation volume is reduced by decrease of the grain size. This reduction which follows a linear relation for UFG specimens, is thought to enhance the required effective (or...