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Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties

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A special issue of Metals (ISSN 2075-4701). This special issue belongs to the section "Metal Casting, Forming and Heat Treatment".

Deadline for manuscript submissions: closed (31 March 2020) | Viewed by 44569

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Special Issue Editors

Dr. Julia Ivanisenko

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Guest Editor

Karlsruhe Institute of Technology, Campus North, Institute of Nanotechnology, Eggenstein-Leopoldshafen, Germany
Interests: severe plastic deformation; nanocrystalline materials; mechanically driven phase transformations; deformation mechanisms in nanocrystalline materials

Dr. Andrea Bachmaier

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Guest Editor

Erich Schmid Institute of Materials Science of the Austrian Academy of Sciences, Jahnstrasse 12, 8700 Leoben, Austria
Interests: generation of metallic nanocomposites and nanocrystalline materials by severe plastic deformation; thermal and mechanical stability of nanocrystalline materials; mechanical alloying; characterisation of NC materials by scanning electron microscopy; transmission electron microscopy and atom probe tomography

Prof. Dr. Thierry Grosdidier

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Professor in Materials Science, Processing and Characterization, Université de Lorraine, Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), CNRS UMR 7239, 7 rue Félix Savart, 57073 Metz, France
Interests: processing and characterisation of ultra-fine grained (UFG) materials; optimisation of metal forming processes; surface engineering and surface treatments; solid state phase transformation and recrystallisation; characterisation of metallic material (electron microscopies, thermophysical analysis, etc.)
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Special Issue Information

Dear Colleagues,

This Special Issue contains the selected papers presented at the 3rd Symposium “Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties”, which is organised as a part of EUROMAT congress in Stockholm, Sweden, September 1–5, 2019. Severe plastic deformation (SPD) is a very attractive research field for metallic materials because it provides new possibilities for manufacturing nanostructured materials in large quantities and allows microstructural design on different hierarchical levels. In addition, through Thermo-Mechanical Processing (TMP) or combinations of TMP and SPD, an ultra-fine-grained structure in bulk materials can be achieved by the refinement of phases using hot, warm, cold, and even cryogenic deformations, or a combination thereof. In addition to grain size refinement, several metallurgical processes which are highly desirable for alloy design take place during SPD. Among them are mechanically driven phase transformations, the formation of metastable phases, grain boundary engineering, and the formation of desirable textures. The papers included in this issue address the following topics: Novel SPD processes as well as recent advancements in established processing methods, deformation mechanisms, microstructure evolution and grain refinement in single- and multi-phase alloys as well as composites, strategies to enhance the microstructure stability at elevated temperatures, mechanically driven phase transformations, surface nanocrystallisation by SPD, gradient and layered nanostructures and multilayered materials, and mechanical and physical properties of SPD-processed materials.

Dr. Julia Ivanisenko
Dr. Andrea Bachmaier
Prof. Dr. Thierry Grosdidier
Guest Editors

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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

Severe plastic deformation
Nanocrystalline and ultrafine-grained materials
Bulk and surface nanocrystallisation
Mechanically driven phase transformations
Mechanical properties
Thermal stability

Published Papers (14 papers)

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Editorial

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4 pages, 188 KiB

Open AccessEditorial

Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties

by Andrea Bachmaier, Thierry Grosdidier and Yulia Ivanisenko

Metals 2020, 10(10), 1306; https://doi.org/10.3390/met10101306 - 29 Sep 2020

Cited by 9 | Viewed by 1679

Abstract

The research field of severe plastic deformation (SPD) offers innovative potential for manufacturing bulk metallic materials as well as for modifying their surfaces [...] Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

Research

Jump to: Editorial

33 pages, 10243 KiB

Open AccessArticle

The Effects of Severe Plastic Deformation and/or Thermal Treatment on the Mechanical Properties of Biodegradable Mg-Alloys

by Andrea Ojdanic, Jelena Horky, Bernhard Mingler, Mattia Fanetti, Sandra Gardonio, Matjaz Valant, Bartosz Sulkowski, Erhard Schafler, Dmytro Orlov and Michael J. Zehetbauer

Metals 2020, 10(8), 1064; https://doi.org/10.3390/met10081064 - 6 Aug 2020

Cited by 14 | Viewed by 3237

Abstract

In this study, five MgZnCa alloys with low alloy content and high biocorrosion resistance were investigated during thermomechanical processing. As documented by microhardness and tensile tests, high pressure torsion (HPT)-processing and subsequent heat treatments led to strength increases of up to 250%; as much as about 1/3 of this increase was due to the heat treatment. Microstructural analyses by electron microscopy revealed a significant density of precipitates, but estimates of the Orowan strength exhibited values much smaller than the strength increases observed. Calculations using Kirchner’s model of vacancy hardening, however, showed that vacancy concentrations of 10⁻⁵ could have accounted for the extensive hardening observed, at least when they formed vacancy agglomerates with sizes around 50–100 nm. While such an effect has been suggested for a selected Mg-alloy already in a previous paper of the authors, in this study the effect was substantiated by combined quantitative evaluations from differential scanning calorimetry and X-ray line profile analysis. Those exhibited vacancy concentrations of up to about 10⁻³ with a marked percentage being part of vacancy agglomerates, which has been confirmed by evaluations of defect specific activation migration enthalpies. The variations of Young’s modulus during HPT-processing and during the subsequent thermal treatments were small. Additionally, the corrosion rate did not markedly change compared to that of the homogenized state. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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16 pages, 4230 KiB

Open AccessFeature PaperArticle

Formation and Thermal Stability of ω-Ti(Fe) in α-Phase-Based Ti(Fe) Alloys

by Mario J. Kriegel, Martin Rudolph, Askar Kilmametov, Boris B. Straumal, Julia Ivanisenko, Olga Fabrichnaya, Horst Hahn and David Rafaja

Metals 2020, 10(3), 402; https://doi.org/10.3390/met10030402 - 21 Mar 2020

Cited by 14 | Viewed by 3848

Abstract

In this work, the formation and thermal stability of the ω-Ti(Fe) phase that were produced by the high-pressure torsion (HPT) were studied in two-phase α-Ti + TiFe alloys containing 2 wt.%, 4 wt.% and 10 wt.% iron. The two-phase microstructure was achieved by annealing the alloys at 470 °C for 4000 h and then quenching them in water. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were utilized to characterize the samples. The thermal stability of the ω-Ti(Fe) phase was investigated using differential scanning calorimetry (DSC) and in situ high-temperature XRD. In the HPT process, the high-pressure ω-Ti(Fe) phase mainly formed from α-Ti. It started to decompose by a cascade of exothermic reactions already at temperatures of 130 °C. The decomposition was finished above ~320 °C. Upon further heating, the phase transformation proceeded via the formation of a supersaturated α-Ti(Fe) phase. Finally, the equilibrium phase assemblage was established at high temperatures. The eutectoid temperature and the phase transition temperatures measured in deformed and heat-treated samples are compared for the samples with different iron concentrations and for samples with different phase compositions prior to the HPT process. Thermodynamic calculations were carried out to predict stable and metastable phase assemblages after heat-treatments at low (α-Ti + TiFe) and high temperatures (α-Ti + β-(Ti,Fe), β-(Ti,Fe)). Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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14 pages, 7654 KiB

Open AccessFeature PaperArticle

Microstructural and Mechanical Stability of a Ti-50.8 at.% Ni Shape Memory Alloy Achieved by Thermal Cycling with a Large Number of Cycles

by Anna Churakova and Dmitry Gunderov

Metals 2020, 10(2), 227; https://doi.org/10.3390/met10020227 - 6 Feb 2020

Cited by 11 | Viewed by 2526

Abstract

The influence of thermal cycling (TC) with a large number of cycles on the microstructure, the parameters of martensitic transformations (MTs), and the mechanical properties of a Ti-50.8 at.% Ni shape-memory alloy in coarse-grained (CG) and ultrafine-grained (UFG) states was investigated. The effect of microstructural and mechanical stability was found in both coarse-grained and ultrafine-grained states starting from the 100th cycle of martensitic transformations. In addition, an unusual temperature change was observed in martensitic transformations occurring with the formation of an intermediate R phase. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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14 pages, 4249 KiB

Open AccessFeature PaperArticle

On the Influence of Ultrasonic Surface Mechanical Attrition Treatment (SMAT) on the Fatigue Behavior of the 304L Austenitic Stainless Steel

by Clément Dureau, Marc Novelli, Mandana Arzaghi, Roxane Massion, Philippe Bocher, Yves Nadot and Thierry Grosdidier

Metals 2020, 10(1), 100; https://doi.org/10.3390/met10010100 - 8 Jan 2020

Cited by 13 | Viewed by 3641

Abstract

The potential of ultrasonic surface mechanical attrition treatment (SMAT) at different temperatures (including cryogenic) for improving the fatigue performance of 304L austenitic stainless steel is evaluated along with the effect of the fatigue loading conditions. Processing parameters such as the vibration amplitude, the size, and the material of the shot medias were fixed. Treatments of 20 min at room temperature and cryogenic temperature were compared to the untreated material by performing rotating–bending fatigue tests at 10 Hz. The fatigue limit was increased by approximately 30% for both peening temperatures. Meanwhile, samples treated for 60 min at room temperature were compared to the initial state in uniaxial fatigue tests performed at R = −1 (fully reversed tension–compression) at 10 Hz, and the fatigue limit enhancement was approximately 20%. In addition, the temperature measurements done during the tests revealed a negligible self-heating (∆t < 50 °C) of the run-out specimens, whereas, at high stress amplitudes, temperature changes as high as 300 °C were measured. SMAT was able to increase the stress range for which no significant local self-heating was reported on the surface. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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12 pages, 10098 KiB

Open AccessArticle

Texture Hardening Observed in Mg–Zn–Nd Alloy Processed by Equal-Channel Angular Pressing (ECAP)

by Jitka Stráská, Peter Minárik, Stanislav Šašek, Jozef Veselý, Jan Bohlen, Robert Král and Jiří Kubásek

Metals 2020, 10(1), 35; https://doi.org/10.3390/met10010035 - 24 Dec 2019

Cited by 15 | Viewed by 2781

Abstract

The addition of Nd significantly improves the mechanical properties of magnesium alloys. However, only limited amounts of Nd or other rare earth (RE) elements should be used due to their high price. In this study, a low-alloyed Mg–1% Zn–1% Nd (ZN11) alloy was designed and processed by hot extrusion and subsequent equal-channel angular pressing (ECAP) in order to achieve a very fine-grained condition with enhanced strength. The microstructure, texture, and mechanical properties were thoroughly studied. The microstructure after 8 passes through ECAP was homogeneous and characterized by an average grain size of 1.5 µm. A large number of tiny secondary phase precipitates were identified as ordered Guinier–Preston (GP) zones. Detailed analysis of the Schmid factors revealed the effect of the texture on deformation mechanisms. ECAP processing more than doubled the achieved yield compression strength (YCS) of the ZN11 alloy. Significant strengthening by ECAP is caused by grain refinement and the formation of ordered Guinier–Preston zones and particles of a secondary γ-phase. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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15 pages, 8416 KiB

Open AccessArticle

On the Use of Functionally Graded Materials to Differentiate the Effects of Surface Severe Plastic Deformation, Roughness and Chemical Composition on Cell Proliferation

by Laurent Weiss, Yaël Nessler, Marc Novelli, Pascal Laheurte and Thierry Grosdidier

Metals 2019, 9(12), 1344; https://doi.org/10.3390/met9121344 - 13 Dec 2019

Cited by 14 | Viewed by 3550

Abstract

Additive manufacturing allows the manufacture of parts made of functionally graded materials (FGM) with a chemical gradient. This research work underlines that the use of FGM makes it possible to study mechanical, microstructural or biological characteristics while minimizing the number of required samples. The application of severe plastic deformation (SPD) by surface mechanical attrition treatment (SMAT) on FGM brings new insights on a major question in this field: which is the most important parameter between roughness, chemistry and microstructure modification on biocompatibility? Our study demonstrates that roughness has a large impact on adhesion while microstructure refinement plays a key role during the early stage of proliferation. After several days, chemistry is the main parameter that holds sway in the proliferation stage. With this respect, we also show that niobium has a much better biocompatibility than molybdenum when alloyed with titanium. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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14 pages, 4067 KiB

Open AccessArticle

Mechanical Properties of Ti-15Mo Alloy Prepared by Cryogenic Milling and Spark Plasma Sintering

by Anna Veverková, Jiří Kozlík, Kristína Bartha, Tomáš Chráska, Cinthia Antunes Corrêa and Josef Stráský

Metals 2019, 9(12), 1280; https://doi.org/10.3390/met9121280 - 28 Nov 2019

Cited by 7 | Viewed by 2733

Abstract

Metastable β-Ti alloy Ti-15Mo was prepared by cryogenic ball milling in a slurry of liquid argon. Material remained ductile even at low temperatures, which suppressed particle refinement, but promoted intensive plastic deformation of individual powder particles. Repetitive deformation of powder particles is similar to the multidirectional rolling and resembles bulk severe plastic deformation (SPD) methods. Initial and milled powders were compacted by spark plasma sintering. Sintered milled powder exhibited a refined microstructure with small β-grains and submicrometer sized α-phase precipitates. The microhardness and the yield tensile strength of the milled powder after sintering at 850 °C attained 350 HV and 1200 MPa, respectively. Low ductility of the material can be attributed to high oxygen content originating from the cryogenic milling. This pioneering work shows that cryogenic milling followed by spark plasma sintering is able to produce two-phase β-Ti alloys with refined microstructure and very high strength levels. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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14 pages, 9706 KiB

Open AccessArticle

Effect of the High-Pressure Torsion (HPT) and Subsequent Isothermal Annealing on the Phase Transformation in Biomedical Ti15Mo Alloy

by Kristína Bartha, Josef Stráský, Anna Veverková, Pere Barriobero-Vila, František Lukáč, Petr Doležal, Petr Sedlák, Veronika Polyakova, Irina Semenova and Miloš Janeček

Metals 2019, 9(11), 1194; https://doi.org/10.3390/met9111194 - 7 Nov 2019

Cited by 14 | Viewed by 2747

Abstract

Ti15Mo metastable beta Ti alloy was solution treated and subsequently deformed by high-pressure torsion (HPT). HPT-deformed and benchmark non-deformed solution-treated materials were annealed at 400 °C and 500 °C in order to investigate the effect of UFG microstructure on the α-phase precipitation. Phase evolution was examined using laboratory X-ray diffraction (XRD) and by high-energy synchrotron X-ray diffraction (HEXRD), which provided more accurate measurements. Microstructure was observed by scanning electron microscopy (SEM) and microhardness was measured for all conditions. HPT deformation was found to significantly enhance the α phase precipitation due the introduction of lattice defects such as dislocations or grain boundaries, which act as preferential nucleation sites. Moreover, in HPT-deformed material, α precipitates are small and equiaxed, contrary to the α lamellae in the non-deformed material. ω phase formation is suppressed due to massive α precipitation and consequent element partitioning. Despite that, HPT-deformed material after ageing exhibits the high microhardness exceeding 450 HV. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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20 pages, 12707 KiB

Open AccessArticle

Tuneable Magneto-Resistance by Severe Plastic Deformation

by Stefan Wurster, Lukas Weissitsch, Martin Stückler, Peter Knoll, Heinz Krenn, Reinhard Pippan and Andrea Bachmaier

Metals 2019, 9(11), 1188; https://doi.org/10.3390/met9111188 - 5 Nov 2019

Cited by 9 | Viewed by 2551

Abstract

Bulk metallic samples were synthesized from different binary powder mixtures consisting of elemental Cu, Co, and Fe using severe plastic deformation. Small particles of the ferromagnetic phase originate in the conductive Cu phase, either by incomplete dissolution or by segregation phenomena during the deformation process. These small particles are known to give rise to granular giant magneto-resistance. Taking advantage of the simple production process, it is possible to perform a systematic study on the influence of processing parameters and material compositions on the magneto-resistance. Furthermore, it is feasible to tune the magneto-resistive behavior as a function of the specimens’ chemical composition. It was found that specimens of low ferromagnetic content show an almost isotropic drop in resistance in a magnetic field. With increasing ferromagnetic content, percolating ferromagnetic phases cause an anisotropy of the magneto-resistance. By changing the parameters of the high pressure torsion process, i.e., sample size, deformation temperature, and strain rate, it is possible to tailor the magnitude of giant magneto-resistance. A decrease in room temperature resistivity of ~3.5% was found for a bulk specimen containing an approximately equiatomic fraction of Co and Cu. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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17 pages, 5716 KiB

Open AccessArticle

Structure and Tensile Strength of Pure Cu after High Pressure Torsion Extrusion

by Dayan Nugmanov, Andrey Mazilkin, Horst Hahn and Yulia Ivanisenko

Metals 2019, 9(10), 1081; https://doi.org/10.3390/met9101081 - 7 Oct 2019

Cited by 13 | Viewed by 3679

Abstract

The microstructure and mechanical properties of rod-shaped samples (measuring 11.8 mm in diameter and 35 mm in length) of commercially pure (CP) copper were characterized after they were processed by high pressure torsion extrusion (HPTE). During HPTE, CP copper was subjected to extremely high strains, ranging from 5.2 at central area of the sample to 22.4 at its edge. This high but varying strain across the sample section resulted in HPTE copper displaying a gradient structure, consisting of fine grains in the central area and of ultrafine grains both in the middle-radius area and at the sample edge. A detailed analysis of the tensile characteristics showed that the strength of HPTE copper with its gradient structure is similar to that of copper after severe plastic deformation (SPD) techniques, typically displaying a homogeneous structure. Detailed analysis of the contributions of various strengthening mechanisms to the overall strength of HPTE coper revealed the following: The main contribution comes from Hall–Petch strengthening due to the presence of high and low angle grain boundaries in gradient structure, which act as effective obstacles to dislocation motion. Therefore, both types of boundaries should be taken into account in the Hall–Petch equation. This study on CP copper demonstrated the potential of using the HPTE method for producing high-strength metallic materials in bulk form for industrial use. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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14 pages, 9988 KiB

Open AccessArticle

Development of a High Strength Mg-9Li Alloy via Multi-Pass ECAP and Post-Rolling

by Edwin Eyram Klu, Dan Song, Chen Li, Guowei Wang, Zhikai Zhou, Bo Gao, Jiapeng Sun, Aibin Ma and Jinghua Jiang

Metals 2019, 9(9), 1008; https://doi.org/10.3390/met9091008 - 14 Sep 2019

Cited by 10 | Viewed by 3253

Abstract

In this study, a high-strength Mg-9Li alloy was developed via multi-pass equal-channel-angular-pressing (ECAP) and post rolling, of which the yield tensile stress (YTS) and ultimate tensile stress (UTS) were 166 MPa and 174 MPa representing about 219% and 70% increase in YTS and UTS respectively, compared to the cast alloy. The cast alloy was ECAP processed at 200 °C for 4, 8, and 16 passes, followed by room-temperature rolling to a total thickness reduction of 50%. The 8-passes ECAPed (E8) alloy presented the best strength of all the ECAPed alloys, and the post rolling endowed the alloy (E8R) further strengthening and the best strength of all the alloys. Grain-boundary strengthening and dislocation strengthening were the two major factors for the high strength of the processed alloys. The α-Mg phase grains were greatly refined to about 2 μm after 8-passes ECAP, and was further refined to about 800 nm ~1.5 μm after rolling. Significant grain refinement endowed the alloy with sufficient grain-boundary strengthening. Profuse intragranular dislocation accumulated in the deformed matrix, leading to the significant dislocation hardening of the alloy. Rolling-induced strong basal texture of the α-Mg phase also enhanced the further strengthening of the E8R alloy. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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9 pages, 4541 KiB

Open AccessArticle

Effect of Severe Plastic Deformation on the Conductivity and Strength of Copper-Clad Aluminium Conductors

by Rimma Lapovok, Michael Dubrovsky, Anna Kosinova and Georgy Raab

Metals 2019, 9(9), 960; https://doi.org/10.3390/met9090960 - 1 Sep 2019

Cited by 11 | Viewed by 4313

Abstract

Aluminium rods with different copper sheath thicknesses were processed by severe plastic deformation at room temperature and then annealed, to join the constituent metals and produce a nanocrystalline microstructure. A study of the effects of the deformation parameters, copper cladding thickness and annealing temperature on the electrical conductivity and hardness of the conductors is reported. It is shown that an interface forms between constituents because of intermixing in the course of severe shear deformation under high hydrostatic pressure and diffusion during the subsequent annealing. The effective conductivity of the aluminium copper-clad conductor dropped after deformation, but was recovered during annealing, especially during short annealing at 200 °C, to a level exceeding the theoretically predicted one. In addition, the annealing resulted in increased hardness at the interface and copper sheath. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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15 pages, 8769 KiB

Open AccessArticle

Improving Strength and Ductility of a Mg-3.7Al-1.8Ca-0.4Mn Alloy with Refined and Dispersed Al₂Ca Particles by Industrial-Scale ECAP Processing

by Ce Wang, Aibin Ma, Jiapeng Sun, Xiaoru Zhuo, He Huang, Huan Liu, Zhenquan Yang and Jinghua Jiang

Metals 2019, 9(7), 767; https://doi.org/10.3390/met9070767 - 9 Jul 2019

Cited by 14 | Viewed by 2797

Abstract

Tailoring the morphology and distribution of the Al₂Ca second phase is important for improving mechanical properties of Al₂Ca-containing Mg-Al-Ca based alloys. This work employed the industrial-scale multi-pass rotary-die equal channel angular pressing (RD-ECAP) on an as-cast Mg-3.7Al-1.8Ca-0.4Mn (wt %) alloy and investigated its microstructure evolution and mechanical properties under three different processing parameters. The obtained results showed that RD-ECAP was effective for refining the microstructure and breaking the network-shaped Al₂Ca phase. With the increase of the ECAP number and decrease of the processing temperature, the average sizes of Al₂Ca particles decreased obviously, and the dispersion of the Al₂Ca phase became more uniform. In addition, more ECAP passes and lower processing temperature resulted in finer α-Mg grains. Tensile test results indicated that the 573 K-12p alloy with the finest and most dispersed Al₂Ca particles exhibited superior mechanical properties with tensile yield strength of 304 MPa, ultimate tensile strength of 354 MPa and elongation of 10.3%. The improved comprehensive mechanical performance could be attributed to refined DRX grains, nano-sized Mg₁₇Al₁₂ precipitates and dispersed Al₂Ca particles, where the refined and dispersed Al₂Ca particles played a more dominant role in strengthening the alloys. Full article

(This article belongs to the Special Issue Severe Plastic Deformation and Thermomechanical Processing: Nanostructuring and Properties)

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