Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.4
2.9
Journals
Metals
Special Issues
Advances in Ultrafine-Grained Metals Research
share announcement

Advances in Ultrafine-Grained Metals Research

A special issue of Metals (ISSN 2075-4701).

Deadline for manuscript submissions: closed (30 June 2020) | Viewed by 11116

Special Issue Editor

Prof. Dr. Marcello Cabibbo

E-Mail Website
Guest Editor
DIISM—Department of Industrial Engineering and Mathematics, Università Politecnica delle Marche, 60131 Via Brecce Bianche, Ancona, Italy
Interests: light alloys (aluminum, magnesium, titanium); steels (carbon-steels, HSLA, TRIP, TWIP, stainless-steels, tool-steels); superalloys (Co-based); nanostructured coatings (DLC, N-based, B-based); severe plastic deformation techniques (ECAP, HPT); hot-deformation (creep, hot torsion); TEM; FEGSEM; XRD; nanoindentation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue aims at presenting the state-of-the-art, and new concepts and principles of UFG obtained by both a top-down approach (SPD) and a bottom-up approach (BM and SPS). In recent years, much progress has been made in the filling of UFG metallic materials for advanced structural and functional use. The newest achievements are mainly associated with the development of novel technological processes for the fabrication of bulk UFG materials using severe plastic deformation (SPD) techniques, and the investigation of fundamental mechanisms leading to improved properties. Great scientific and technologic interest is based on the fact that grain size can be regarded as a key microstructural factor affecting nearly all aspects of the physical and mechanical behaviour of polycrystalline metals. Hence, control over grain size has long been recognized as a way to design materials with desired properties. Most of the mechanical and chemical-physical properties benefit greatly from grain size reduction. As the race for better materials performance is never ending, attempts to develop viable techniques for microstructure refinement continue. The contributions of the present Special Issue include the different major techniques nowadays in use to produce sound and reliable UFG metallic materials. These include light alloys and steels.

Prof. Marcello Cabibbo
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Metals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Ultrafine-grained metals
  • Severe Plastic Deformation (SPD)
  • Top-down approach
  • Bottom-up approach
  • Equal-Channel Angular Pressing (ECAP)
  • Hot-Pressure Torsion (HPT)
  • Accumulative Roll Bonding (ARB)
  • Ball Milling (BM)
  • Spark-Plasma Sintering (SPS)

Published Papers (4 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

16 pages, 2588 KiB  
Article
Early Stages of Plastic Deformation in Low and High SFE Pure Metals
by Marcello Cabibbo and Eleonora Santecchia
Metals 2020, 10(6), 751; https://0-doi-org.brum.beds.ac.uk/10.3390/met10060751 - 05 Jun 2020
Cited by 2 | Viewed by 2346
Abstract
Severe plastic deformation (SPD) techniques are known to promote exceptional mechanical properties due to their ability to induce significant grain and cell size refinement. Cell and grain refinement are driven by continuous newly introduced dislocations and their evolution can be followed at the [...] Read more.
Severe plastic deformation (SPD) techniques are known to promote exceptional mechanical properties due to their ability to induce significant grain and cell size refinement. Cell and grain refinement are driven by continuous newly introduced dislocations and their evolution can be followed at the earliest stages of plastic deformation. Pure metals are the most appropriate to study the early deformation processes as they can only strengthen by dislocation rearrangement and cell-to-grain evolution. However, pure metals harden also depend on texture evolution and on the metal stacking fault energy (SFE). Low SFE metals (i.e., copper) strengthen by plastic deformation not only by dislocation rearrangements but also by twinning formation within the grains. While, high SFE metals, (i.e., aluminium) strengthen predominantly by dislocation accumulation and rearrangement with plastic strain. Thence, in the present study, the early stages of plastic deformation were characterized by transmission electron microscopy on pure low SFE Oxygen-Free High Conductivity (OFHC) 99.99% pure Cu and on a high SFE 6N-Al. To induce an almost continuous rise from very-low to low plastic deformation, the two pure metals were subjected to high-pressure torsion (HPT). The resulting strengthening mechanisms were modelled by microstructure quantitative analyses carried out on TEM and then validated through nanoindentation measurements. Full article
(This article belongs to the Special Issue Advances in Ultrafine-Grained Metals Research)
►▼ Show Figures

Figure 1

10 pages, 5263 KiB  
Article
Microstructures and Hardness Prediction of an Ultrafine-Grained Al-2024 Alloy
by Ying Chen, Yuanchen Tang, Houan Zhang, Nan Hu, Nong Gao and Marco J. Starink
Metals 2019, 9(11), 1182; https://0-doi-org.brum.beds.ac.uk/10.3390/met9111182 - 01 Nov 2019
Cited by 8 | Viewed by 3094
Abstract
High-pressure torsion (HPT) is a high efficiency processing method for fabricating bulk ultrafine-grained metallic materials. This work investigates microstructures and evaluates the corresponding strengthening components in the center of HPT disks, where effective shear strains are very low. An Al-4.63Cu-1.51Mg (wt. %) alloy [...] Read more.
High-pressure torsion (HPT) is a high efficiency processing method for fabricating bulk ultrafine-grained metallic materials. This work investigates microstructures and evaluates the corresponding strengthening components in the center of HPT disks, where effective shear strains are very low. An Al-4.63Cu-1.51Mg (wt. %) alloy was processed by HPT for 5 rotations. Non-equilibrium grain and sub-grain boundaries were observed using scanning transmission electron microscopy in the center area of HPT disks. Solute co-cluster segregation at grain boundaries was found by energy dispersive spectrometry. Quantitative analysis of X-ray diffraction patterns showed that the average microstrain, crystalline size, and dislocation density were (1.32 ± 0.07) × 10−3, 61.9 ± 1.4 nm, and (2.58 ± 0.07) × 1014 m−2, respectively. The ultra-high average hardness increment was predicted on multiple mechanisms due to ultra-high dislocation densities, grain refinement, and co-cluster–defect complexes. Full article
(This article belongs to the Special Issue Advances in Ultrafine-Grained Metals Research)
►▼ Show Figures

Figure 1

12 pages, 4111 KiB  
Article
Investigation on the Strain Distribution in Tube High-Pressure Shearing
by Jia Jie Meng, Zheng Li, Ying Liu, Ye Bin Zhu, Shun Wang, Kui Lin, Jia Qiang Tao and Jing Tao Wang
Metals 2019, 9(10), 1117; https://0-doi-org.brum.beds.ac.uk/10.3390/met9101117 - 19 Oct 2019
Cited by 8 | Viewed by 2118
Abstract
The Finite-element method (FEM) and experiments were used to investigate the geometric factors and material parameter on the strain distribution during tube high-pressure shearing (t-HPS). The results show that t-HPS could be realized successfully either by pressurizing on both ends [...] Read more.
The Finite-element method (FEM) and experiments were used to investigate the geometric factors and material parameter on the strain distribution during tube high-pressure shearing (t-HPS). The results show that t-HPS could be realized successfully either by pressurizing on both ends of the tube, or by pressurizing using the wedge effect; and in both cases, the “dead metal zone” could be found at both ends of the tube. The grain size distribution from the experiment confirmed this strain distribution feature. In the case of t-HPS pressurized using the wedge effect, the half cone angle has little effect on the strain distribution. Decreasing the strain-hardening exponent leads to increased deformation inhomogeneity in both the ideal t-HPS described by theoretical equations and the close to practical t-HPS described by FEM. This feature of t-HPS stands out from other SPD processes like HPT, and makes practical t-HPS behavior more predictable using the analytical formation than any other SPD processes, and places it an advantageous position in understanding the basics of deformation physics through the coupling between practical experiments and theoretical approaches. Full article
(This article belongs to the Special Issue Advances in Ultrafine-Grained Metals Research)
►▼ Show Figures

Figure 1

12 pages, 3978 KiB  
Article
Grain Size Effect on the Mechanical Behavior of Metastable Fe-23Cr-8.5Ni Alloy
by Lin Xie, Chunpeng Wang, Yuhui Wang, Guilin Wu and Xiaoxu Huang
Metals 2019, 9(7), 734; https://0-doi-org.brum.beds.ac.uk/10.3390/met9070734 - 29 Jun 2019
Cited by 9 | Viewed by 2697
Abstract
An Fe-23Cr-8.5Ni alloy was used as a model material to study the grain size effect on the mechanical behavior of metastable duplex metal. Alloy samples with different grain sizes ranging from 0.1 to 2 μm were prepared by cold-rolling and annealing. A structural [...] Read more.
An Fe-23Cr-8.5Ni alloy was used as a model material to study the grain size effect on the mechanical behavior of metastable duplex metal. Alloy samples with different grain sizes ranging from 0.1 to 2 μm were prepared by cold-rolling and annealing. A structural refinement to about 0.1 μm results in a high yield strength but very limited ductility. A significant improvement of ductility occurred at the grain size of about 0.4 μm. A further increase in grain size results in a decreased strength and a slightly improved ductility. The alloy with a grain size of about 0.4 μm exhibits an excellent combination of strength and ductility, where the yield strength and tensile elongation are increased up to 738 MPa and 29% as compared to 320 MPa and 33% of a coarse-grained (about 2 μm) sample, respectively. The origin of the excellent mechanical properties was attributed to the unique deformation characteristics associated with the transformation induced plasticity and the development of back stress. Full article
(This article belongs to the Special Issue Advances in Ultrafine-Grained Metals Research)
►▼ Show Figures

Graphical abstract

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-4
Back to TopTop