Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.2
2.4
Journals
Crystals
Special Issues
Deformation and Recrystallization Behaviour of Alloys
share announcement

Deformation and Recrystallization Behaviour of Alloys

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Crystalline Metals and Alloys".

Deadline for manuscript submissions: closed (10 October 2023) | Viewed by 6075

Special Issue Editors

Dr. Ali Arab

E-Mail Website
Guest Editor
Advanced Technology Research Institute, Beijing Institute of Technology, Jinan 250300, China
Interests: mechanics of materials; high strain rate; high entropy alloys; titanium
Prof. Baoqiao Guo

E-Mail Website
Guest Editor
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China
Interests: experimental mechanics; digital image correlation; mechanics of materials
Dr. Bin Jia

E-Mail Website
Guest Editor
Department of Mechanics, College of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China
Interests: ballistic impact behavior of structures; gradient nanostructured materials; explosive welding
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Rusinek Alexis

E-Mail Website
Guest Editor
Laboratory of Microstructure Studies and Mechanics of Materials, UMR-CNRS 7239, Lorraine University, 57073 Metz, France
Interests: austenitic stainless steel; the mechanical behaviour of additively manufactured alloys; impact dynamics

Special Issue Information

Dear Colleagues,

Recrystallization is a very pervasive transformation phenomenon that is  very important in microstructure designs. RX could be defined as the formation of a new grain structure in deformed materials through the formation and migration of high angle grain boundaries driven by the stored energy of deformation. The process of RX of plastically deformed metals and alloys is of central importance in the processing of metallic alloys.

Deformation processing and material factors such as stress accumulation, inhomogeneous strain distribution, stored energy, available slip systems, microstructural variability, initial grain size, phase composition, texture, stacking fault and lattice distortion energies, strain rate, and deformation temperature are at play in determining recrystallization mechanisms and kinetics in alloys.
In this Special Issue, we aim to provide a wide spectrum of articles dealing with the RX phenomenon via experimental or modeling methods. In particular, submissions that combine experimental observations with numerical simulations are encouraged. In addition, studies that aim to develop suitable experimental methods for describing and characterizing RX are welcome.

Dr. Ali Arab
Dr. Baoqiao Guo
Dr. Bin Jia
Prof. Dr. Rusinek Alexis
Guest Editors

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. Crystals 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 2100 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

  • recrystallization
  • high strain rate deformation
  • hot deformation
  • dynamic recrystallization
  • adiabatic shear band

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

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

23 pages, 26158 KiB  
Article
Investigation of the Hot Deformation Behavior and Mechanism of a Medium-Entropy CoCr0.4NiSi0.3 Alloy
by Li Zhang, Hui Zhao, Lijia Chen, Feng Li, Weiqiang Zhang, Ge Zhou, Haoyu Zhang and Ningning Geng
Crystals 2024, 14(1), 3; https://doi.org/10.3390/cryst14010003 - 19 Dec 2023
Cited by 2 | Viewed by 1109
Abstract
The CoCrNi-based medium-entropy alloys (MEA) have been extensively investigated due to their exceptional mechanical properties at both room and cryogenic temperatures. To investigate the hot deformation behavior and the recrystallization mechanism of the CoCr0.4NiSi0.3 medium-entropy alloy, a series of deformation [...] Read more.
The CoCrNi-based medium-entropy alloys (MEA) have been extensively investigated due to their exceptional mechanical properties at both room and cryogenic temperatures. To investigate the hot deformation behavior and the recrystallization mechanism of the CoCr0.4NiSi0.3 medium-entropy alloy, a series of deformation tests was conducted using the MMS-100 thermal simulation tester, with deformation conditions of 0.001–1 s−1/850–1150 °C. During the hot deformation process, the flow stress initially increases up to its peak value before gradually decreasing towards a steady state level. Higher flow stress levels are observed with increasing strain rate and decreasing deformation temperature. The estimated activation energy for hot deformation of this alloy is approximately 423.6602 kJ/mol. The Arrhenius-type constitutive equation is utilized to establish a modified model while incorporating power dissipation theory and the instability criterion of a dynamic material model to construct power dissipation maps and instability maps. By superimposing these maps, hot processing maps with strains of 0.4, 0.5, and 0.7 are derived. In this investigation, it is observed that regions of instability exclusively occur when the true strain exceeds 0.4. These regions of instability on the hot processing map align well with experimental findings. The suitable range of parameters for hot-working decreases as the true strain increases. The microstructure was analyzed using electron backscatter diffraction and transmission electron microscopy (TEM) techniques. The volume fraction of dynamic recrystallization (DRX) decreases with increasing strain rate but diminishes with rising temperature. The TEM characterization elucidated the mechanism of DRX in this MEA. The presence of the long-period stacking ordered (LPSO) phase was observed in both the face-centered cubic matrix and hexagonal close-packed recrystallized grains under different deformation conditions. The LPSO phase originates from the matrix at a low strain rate, whereas it is generated during recrystallization at a high strain rate. The observed increase in flow stress of the as-cast MEA is primarily attributed to the synergistic effects arising from the interaction of the dislocation with twins and the second phase. The onset of instability is effectively suppressed within a limited range through the formation of coherent second phases such as L12, LPSO, and superlattice structures resulting from phase transitions. These second phases serve as nucleation sites for recrystallization and contribute to the strengthening of dispersion. Furthermore, their interaction with dislocations and twins significantly influences both flow stress behavior and recrystallization kinetics under hot deformation. These findings not only deepen our understanding of the underlying deformation mechanisms governing MEA but also offer valuable insights for designing CoCrNi-based alloys with improved mechanical properties at elevated temperatures. Full article
(This article belongs to the Special Issue Deformation and Recrystallization Behaviour of Alloys)
►▼ Show Figures

Figure 1

10 pages, 3880 KiB  
Article
Coercivity Enhancement of Sintered Nd-Pr-Fe-B Magnets by Cost-Effective Grain Boundary Diffusion of Dy/Tb Films
by Xin-De Zhu, Mei Wang, Yong-Jiang Yu, Qian Wang, Fei Wang, Peng-Fei Wang, Bin Jia, Cong Wang and Bin Zhou
Crystals 2023, 13(10), 1516; https://doi.org/10.3390/cryst13101516 - 19 Oct 2023
Viewed by 1464
Abstract
High-performance sintered Nd-Pr-Fe-B magnets were successfully prepared by depositing Dy/Tb films on the surface using magnetron sputtering, which resulted in superior grain boundary diffusion (GBD) under heat treatments. The course of the diffusion was assessed using an electron probe microanalyzer (EPMA) and inductively [...] Read more.
High-performance sintered Nd-Pr-Fe-B magnets were successfully prepared by depositing Dy/Tb films on the surface using magnetron sputtering, which resulted in superior grain boundary diffusion (GBD) under heat treatments. The course of the diffusion was assessed using an electron probe microanalyzer (EPMA) and inductively coupled plasma (ICP). The magnetic properties and thermal stability of the magnets before and after diffusion were investigated. The results show that, mainly due to the increased and optimized Nd-Pr-rich phases and the formation of the (Nd,Pr,Dy/Tb)2Fe14B shell structure surrounding the (Nd,Pr)2Fe14B grains, the coercivity of the Dy- and Tb-diffused magnets was enhanced from 16.7 kOe to 24.8 kOe and 28.4 kOe, respectively, while the corresponding maximum energy product (BHmax) was 48.1 MGOe and 48.5 MGOe, respectively. The consumption of Dy/Tb in this work (0.35 wt% Dy in the Dy-diffused magnet and 0.42 wt% Tb in the Tb-diffused magnet) is much lower than that of previously reported magnets with comparable coercivity. Furthermore, Dy- or Tb-diffused magnets exhibit better thermal stability than that of the original magnet, owing to the better resistance to thermal disturbances of the magnets with optimized microstructure. This work can provide useful guidance for preparing Nd-Fe-B magnets with low cost and high performance. Full article
(This article belongs to the Special Issue Deformation and Recrystallization Behaviour of Alloys)
►▼ Show Figures

Figure 1

16 pages, 3354 KiB  
Article
Microstructure Effects on the Machinability of AM-Produced Superalloys
by Paul Wood, José Díaz-Álvarez, Alexis Rusinek, Urvashi Gunputh, Slim Bahi, Antonio Díaz-Álvarez, Maria Henar Miguélez, Yiling Lu, Pawel Platek and Judyta Sienkiewicz
Crystals 2023, 13(8), 1190; https://doi.org/10.3390/cryst13081190 - 31 Jul 2023
Cited by 4 | Viewed by 1668
Abstract
This paper discusses the microstructure effects on the machinability of Inconel 718 by conducting machining tests on an additively manufactured (AM) workpiece with a strongly textured grain structure and a wrought workpiece incorporating a finer and more equiaxed grain structure. The AM workpiece [...] Read more.
This paper discusses the microstructure effects on the machinability of Inconel 718 by conducting machining tests on an additively manufactured (AM) workpiece with a strongly textured grain structure and a wrought workpiece incorporating a finer and more equiaxed grain structure. The AM workpiece was produced as a thin tube using Laser Melting Powder Bed Fusion and optimal processing conditions for this alloy. A lathe was used to conduct instrumented orthogonal machining tests on the two workpiece materials under dry cut and coolant conditions using a semisynthetic emulsion coolant. The process parameters studied were feed from 0.05 to 0.15 mm/rev and cutting speed from 60 to 120 m/min with a cut time of 2 sec duration for each process condition. Measures for each process condition included cutting forces in the feed and main cut direction, and images of chip forms were obtained. The grain structures of the workpiece materials were characterized using Electron Back Scattered Diffraction (EBSD). New findings suggest that grain structures can significantly affect the machinability of the superalloy at a higher feed for all cutting speeds studied, and insights into the cause are discussed. Other important findings comment on the effectiveness of the coolant as a lubricant for reducing friction in machining. Full article
(This article belongs to the Special Issue Deformation and Recrystallization Behaviour of Alloys)
►▼ Show Figures

Figure 1

14 pages, 5650 KiB  
Article
Use of Digital Image Correlation (DIC) to Improve the Critical Strain-Annealing (CSA) Method for Producing Large Crystals: Application to A1050 Commercially Pure Aluminum
by Halim Haddadi, Hoang-Son Tran and Patrick Franciosi
Crystals 2023, 13(6), 923; https://doi.org/10.3390/cryst13060923 - 8 Jun 2023
Cited by 1 | Viewed by 1256
Abstract
The aim of this work is to present an efficient procedure for growing large metallic single crystals that associates a classical growth technique (namely, the critical strain-annealing—CSA—method) with advanced methods of accurate full-field strain measurements based on digital image correlation (DIC) technique and [...] Read more.
The aim of this work is to present an efficient procedure for growing large metallic single crystals that associates a classical growth technique (namely, the critical strain-annealing—CSA—method) with advanced methods of accurate full-field strain measurements based on digital image correlation (DIC) technique and of sample geometry design using finite element analysis. Measuring the critical plastic strains with an accuracy better than 0.1% resulted in a significantly improved construction of the recrystallization diagram. Applying this “DIC-assisted CSA method” to an A1050 commercially pure aluminum allowed obtaining in less than two days (26 h to 30 h) large multi-crystal samples with a half dozen of large grains. Their length between 35 mm and 100 mm was in full agreement with the obtained recrystallization diagram. Full article
(This article belongs to the Special Issue Deformation and Recrystallization Behaviour of Alloys)
►▼ Show Figures

Figure 1

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