Next Issue
Volume 2, March
 
 

Metals, Volume 1, Issue 1 (December 2011) – 7 articles , Pages 1-112

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Select all
Export citation of selected articles as:
2698 KiB  
Article
Impact Response of Aluminum Foam Sandwiches for Light-Weight Ship Structures
by Vincenzo Crupi, Gabriella Epasto and Eugenio Guglielmino
Metals 2011, 1(1), 98-112; https://doi.org/10.3390/met1010098 - 15 Dec 2011
Cited by 48 | Viewed by 11368
Abstract
The structures realized using sandwich technologies combine low weight with high energy absorbing capacity, so they are suitable for applications in the transport industry (automotive, aerospace, shipbuilding industry) where the “lightweight design” philosophy and the safety of vehicles are very important aspects. While [...] Read more.
The structures realized using sandwich technologies combine low weight with high energy absorbing capacity, so they are suitable for applications in the transport industry (automotive, aerospace, shipbuilding industry) where the “lightweight design” philosophy and the safety of vehicles are very important aspects. While sandwich structures with polymeric foams have been applied for many years, currently there is a considerable and growing interest in the use of sandwiches with aluminum foam core. The aim of this paper was the analysis of low-velocity impact response of AFS (aluminum foam sandwiches) panels and the investigation of their collapse modes. Low velocity impact tests were carried out by a drop test machine and a theoretical approach, based on the energy balance model, has been applied to investigate their impact behavior. The failure mode and the internal damage of the impacted AFS have also been investigated by a Computed Tomography (CT) system. Full article
(This article belongs to the Special Issue Metal Foams)
Show Figures

7679 KiB  
Article
Ti-Al Composite Wires with High Specific Strength
by Tom Marr, Jens Freudenberger, Dirk Seifert, Hansjörg Klauß, Jan Romberg, Ilya Okulov, Juliane Scharnweber, Andy Eschke, Carl-Georg Oertel, Werner Skrotzki, Uta Kühn, Jürgen Eckert and Ludwig Schultz
Metals 2011, 1(1), 79-97; https://doi.org/10.3390/met1010079 - 17 Nov 2011
Cited by 17 | Viewed by 9941
Abstract
An alternative deformation technique was applied to a composite made of titanium and an aluminium alloy in order to achieve severe plastic deformation. This involves accumulative swaging and bundling. Furthermore, it allows uniform deformation of a composite material while producing a wire which [...] Read more.
An alternative deformation technique was applied to a composite made of titanium and an aluminium alloy in order to achieve severe plastic deformation. This involves accumulative swaging and bundling. Furthermore, it allows uniform deformation of a composite material while producing a wire which can be further used easily. Detailed analysis concerning the control of the deformation process, mesostructural and microstructural features and tensile testing was carried out on the as produced wires. A strong grain refinement to a grain size of 250–500 nm accompanied by a decrease in 〈111〉 fibre texture component and a change from low angle to high angle grain boundary characteristics is observed in the Al alloy. A strong increase in the mechanical properties in terms of ultimate tensile strength ranging from 600 to 930 MPa being equivalent to a specific strength of up to 223 MPa/g/cm3 was achieved. Full article
Show Figures

2030 KiB  
Article
Particle Based Alloying by Accumulative Roll Bonding in the System Al-Cu
by Christian W. Schmidt, Patrick Knödler, Heinz Werner Höppel and Mathias Göken
Metals 2011, 1(1), 65-78; https://doi.org/10.3390/met1010065 - 07 Nov 2011
Cited by 19 | Viewed by 9393
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Processing and Properties of Bulk Nanostructured Materials)
Show Figures

5418 KiB  
Article
The Manufacture and Characterisation of Aluminium Foams Made by Investment Casting Using Dissolvable Spherical Sodium Chloride Bead Preforms
by Apichart Jinnapat and Andrew Kennedy
Metals 2011, 1(1), 49-64; https://doi.org/10.3390/met1010049 - 04 Nov 2011
Cited by 28 | Viewed by 9639
Abstract
Open cell Al foams have been made by infiltrating molten Al into preforms made from porous salt spheres. Infiltration has been effected using simple pressure-assisted vacuum investment casting where the maximum infiltration pressure difference was less than 36 psi. The preform and resulting [...] Read more.
Open cell Al foams have been made by infiltrating molten Al into preforms made from porous salt spheres. Infiltration has been effected using simple pressure-assisted vacuum investment casting where the maximum infiltration pressure difference was less than 36 psi. The preform and resulting foam density decreased with increasing compaction pressure and the foam density increased with increasing infiltration pressure. For low pressure infiltration, and high density preforms, salt dissolution was rapid due to the porous nature of the salt spheres. Infiltration of molten Al occurred into the beads and, for high density preforms and higher infiltration pressures, the volume of metal in the beads exceeded that in the cell walls, drastically decreasing the NaCl dissolution rate. A simple approach is shown whereby the data from mercury porosimetry can be used to predict the resulting foam density, thereby aiding the design of preform and beads structures. Full article
(This article belongs to the Special Issue Metal Foams)
Show Figures

495 KiB  
Review
Approaches to Modeling of Recrystallization
by Håkan Hallberg
Metals 2011, 1(1), 16-48; https://doi.org/10.3390/met1010016 - 28 Oct 2011
Cited by 135 | Viewed by 17150
Abstract
Control of the material microstructure in terms of the grain size is a key component in tailoring material properties of metals and alloys and in creating functionally graded materials. To exert this control, reliable and efficient modeling and simulation of the recrystallization process [...] Read more.
Control of the material microstructure in terms of the grain size is a key component in tailoring material properties of metals and alloys and in creating functionally graded materials. To exert this control, reliable and efficient modeling and simulation of the recrystallization process whereby the grain size evolves is vital. The present contribution is a review paper, summarizing the current status of various approaches to modeling grain refinement due to recrystallization. The underlying mechanisms of recrystallization are briefly recollected and different simulation methods are discussed. Analytical and empirical models, continuum mechanical models and discrete methods as well as phase field, vertex and level set models of recrystallization will be considered. Such numerical methods have been reviewed previously, but with the present focus on recrystallization modeling and with a rapidly increasing amount of related publications, an updated review is called for. Advantages and disadvantages of the different methods are discussed in terms of applicability, underlying assumptions, physical relevance, implementation issues and computational efficiency. Full article
(This article belongs to the Special Issue Processing and Properties of Bulk Nanostructured Materials)
Show Figures

1143 KiB  
Article
Evolution of Morphology and Microstructure in Electrodeposited Nanocrystalline Al–Mg Alloy Dendrites
by Sankara Sarma V. Tatiparti and Fereshteh Ebrahimi
Metals 2011, 1(1), 3-15; https://doi.org/10.3390/met1010003 - 05 Sep 2011
Cited by 5 | Viewed by 7502
Abstract
Nanocrystalline Al–Mg dendrites were fabricated through galvanostatic electrodeposition. Initially feather-like morphology was formed exhibiting morphological evolution to smooth globules at its tips. With eventual deposition, rough globules formed over the smooth ones. The feather-like and smooth globules possessed supersaturated face centered cubic (fcc)–Al(Mg) [...] Read more.
Nanocrystalline Al–Mg dendrites were fabricated through galvanostatic electrodeposition. Initially feather-like morphology was formed exhibiting morphological evolution to smooth globules at its tips. With eventual deposition, rough globules formed over the smooth ones. The feather-like and smooth globules possessed supersaturated face centered cubic (fcc)–Al(Mg) phase with ~7 and ~20 at.% Mg respectively. The rough globules contained hexagonal close packed (hcp)–Mg(Al) phase with ~80 at.% Mg. Microstructural examinations revealed that the feather-like and rough globules possessed grain sizes of ~42 ± 15 and ~36 ± 12 nm respectively. The region, which exhibited morphological evolution from feather-like to smooth globules, possessed ~16 ± 7 nm grain size. The observed microstructural and compositional features were attributed to the local current density values. The formation of the Al–Mg dendrites is discussed in this paper. Full article
(This article belongs to the Special Issue Nanocrystalline Metals and Alloys)
Show Figures

36 KiB  
Editorial
Welcome to Metals––a New Open Access Journal for a Growing Scientific Community
by Hugo F. López
Metals 2011, 1(1), 1-2; https://doi.org/10.3390/met1010001 - 25 Feb 2011
Cited by 27 | Viewed by 4999
Abstract
As I assume the role of Editor-in-Chief of this new journal, I look forward to serving in contributing to the advance of science and engineering in the field of metallic materials. This formidable task is made possible thanks to the excellent support of [...] Read more.
As I assume the role of Editor-in-Chief of this new journal, I look forward to serving in contributing to the advance of science and engineering in the field of metallic materials. This formidable task is made possible thanks to the excellent support of the Publisher and of the Editorial Staff of MDPI, as well as to a highly qualified Editorial Board. Hence, it is with pleasure that I accept this challenge, and I look forward to work with all of you in expanding the field of metals through journal contributions of current importance and of great interest to the scientific community. [...] Full article
Next Issue
Back to TopTop