Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.5
2.7
Journals
Applied Sciences
Special Issues
Thermomechanical Properties of Steel
share announcement

Thermomechanical Properties of Steel

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Mechanical Engineering".

Deadline for manuscript submissions: closed (30 April 2021) | Viewed by 19642

Special Issue Editor

Dr. Bernd Kuhn

E-Mail Website
Guest Editor
Forschungszentrum Juelich GmbH, Microstructure and Properties of Materials (IEK-2), Insititute of Energy and Climate Research (IEK), Jülich, Germany
Interests: alloy development; thermomechanical fatigue; fracture mechanics; creep; stress relaxation; metallic high temperature alloys
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In numerous branches of science, state-of-the-art materials are operated close to their application limits today. For example, the advancement of thermal power generation efficiency was governed for decades by the further development of the ferritic–martensitic (FM) 9 - 12 Cr steel grades, which enabled a great rise in plant efficiency over a period of 60 years, but which has stagnated since the 1990s. All attempts to combine sufficient creep strength and increased steam oxidation resistance in new FM steels at temperatures beyond 620 °C have failed so far. Furthermore, the transition of the generation sector towards regenerative power supply poses a lot of new challenges for structural high-temperature materials, because operation modes change from mainly base load to flexible residual load compensation operation, which leads to strongly increased demand for structural steels designed against fatigue damage.

Another example are martensitic hot-working die steels applied, for example, in the production of automotive chassis parts from high-strength TRIP and TWIP steels. The durability of such martensitic stamping tools is strongly limited because it lacks both  mechanical long-term strength and oxidation resistance at temperatures exceeding 620 °C. Furthermore, such stamping tools are subject to severe thermomechanical loading. Low-cost, carbide/nitride-strengthened, martensitic steels thus seem to hit tough technological limits, and alternatives are strongly desired.

Successful development under tough technological limitations necessitates an integral, innovative approach concerning specification, development, processing, and testing. This Special Issue is dedicated to the latest advances made in low-cost structural steels. These advances cover novel steel grades and processing techniques, microstructure and property determination, and possible applications in all fields of industry.

Dr.-Ing. Bernd Kuhn
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. Applied Sciences is an international peer-reviewed open access semimonthly 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 2400 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

  • alloy development
  • processing
  • heat treatment
  • microstructure property relations
  • mechanical properties
  • fatigue
  • thermomechanical fatigue

Published Papers (10 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

17 pages, 73519 KiB  
Article
Influence of Thermomechanical Treatments on Corrosion of Carbon Steel in Synthetic Geopolymer Fly Ash Pore Solution
by Juan Bosch, Ulises Martin, Jacob Ress, Keston Klimek and David M. Bastidas
Appl. Sci. 2021, 11(9), 4054; https://0-doi-org.brum.beds.ac.uk/10.3390/app11094054 - 29 Apr 2021
Cited by 5 | Viewed by 1715
Abstract
In this study the effect of thermomechanical treatments in chloride induced pitting corrosion is presented for carbon steel rebars exposed to synthetic fly ash (FA) pore solution. Due to the likely phase transformations that steel reinforcements in concrete experience during the event of [...] Read more.
In this study the effect of thermomechanical treatments in chloride induced pitting corrosion is presented for carbon steel rebars exposed to synthetic fly ash (FA) pore solution. Due to the likely phase transformations that steel reinforcements in concrete experience during the event of a fire, the understanding of the corrosion behavior of such phases is key in predicting the stability of the structure. The motivation for this study arrives from the scarce literature regarding the corrosion behavior of thermomechanically treated steel reinforcements in FA environments and the need for further investigation to understand its mechanism. In order to better understand the effects on the corrosion behavior electrochemical measurements including cyclic potentiodynamic polarization curves (CPP) and electrochemical impedance spectroscopy (EIS) were used. It was found that quenched specimens showed enhanced corrosion kinetics as their icorr values were higher, being of 3.18 × 10−5 and 2.20 × 10−5 A/cm2 for water and oil quenched compared to 2.13 × 10−6 A/cm2 for the as-received. Furthermore, the effective capacitance of the double layer (Ceff,dl) showed the lower stability of the passive film for the quenched specimens, with values of 1.11 × 10−3 µF/cm2 for the as-receive sample that decreased to 8.12 × 10−4 µF/cm2 for the water quenched sample. The anodic charge transfer coefficient in the synthetic FA alkaline pore solution changes from 0.282 to 0.088, for the as-received and water quenched rebars specimens, respectively. These results indicate a lower energy barrier for the anodic dissolution reaction of quenched specimens, indicating that martensite and bainite microstructures promote corrosion process. Enhanced corrosion was found on quenched samples presenting martensite and bainite microstructure as showed by the increased pith depth, with values of 5 μm compared to 1 μm observed in the as-received samples. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

13 pages, 8676 KiB  
Article
The Investigation of Microstructure and Mechanical Behavior and the Fractographic Analysis of the Ti49.1Ni50.9 Alloy in States with Different Activation Deformation Volumes
by Anna Churakova, Dmitry Gunderov and Elina Kayumova
Appl. Sci. 2021, 11(7), 3052; https://0-doi-org.brum.beds.ac.uk/10.3390/app11073052 - 29 Mar 2021
Viewed by 1303
Abstract
In this article, the microstructure and mechanical behavior of the Ti49.1Ni50.9 alloy with a high content of nickel in a coarse-grained state, obtained by quenching, ultrafine-grained (obtained through the equal-channel angular pressing (ECAP) method) and nanocrystalline (high pressure torsion (HPT) [...] Read more.
In this article, the microstructure and mechanical behavior of the Ti49.1Ni50.9 alloy with a high content of nickel in a coarse-grained state, obtained by quenching, ultrafine-grained (obtained through the equal-channel angular pressing (ECAP) method) and nanocrystalline (high pressure torsion (HPT) + annealing), were investigated using mechanical tensile tests at different temperatures. Mechanical tests at different strain rates for determining the parameter of strain rate sensitivity m were carried out. Analysis of m showed that with an increase in the test temperature, an increase in this parameter was observed for all studied states. In addition, this parameter was higher in the ultrafine-grained state than in the coarse-grained state. The activation deformation volume in the ultrafine-grained state was 2–3 times greater than in the coarse-grained state at similar tensile temperatures. Fractographic analysis of samples after mechanical tests was carried out. An increase in the test temperature led to a change in the nature of fracture from quasi-brittle–brittle (with small pits) at room temperature to ductile (with clear dimples) at elevated temperatures. Microstructural studies were carried out after the tensile tests at different temperatures, showing that at elevated test temperatures, the matrix was depleted in nickel with the formation of martensite twins. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

13 pages, 6602 KiB  
Article
Effect of Different Precipitation Routes of Fe2Hf Laves Phase on the Creep Rate of 9Cr-Based Ferritic Alloys
by Satoru Kobayashi and Toru Hara
Appl. Sci. 2021, 11(5), 2327; https://0-doi-org.brum.beds.ac.uk/10.3390/app11052327 - 05 Mar 2021
Cited by 6 | Viewed by 1305
Abstract
We performed creep tests for three types of Fe-9Cr-Hf alloys with a ferritic matrix w/o Fe2Hf Laves phase particles formed by two precipitation routes: (1) with fine Fe2Hf particles formed by the conventional precipitation route (hereafter the particles are [...] Read more.
We performed creep tests for three types of Fe-9Cr-Hf alloys with a ferritic matrix w/o Fe2Hf Laves phase particles formed by two precipitation routes: (1) with fine Fe2Hf particles formed by the conventional precipitation route (hereafter the particles are called CP particles), namely formed in the α-ferrite matrix after γ-austenite → α-ferrite phase transformation; (2) with fine Fe2Hf particles formed by interphase precipitation (hereafter called IP particles) during δ-ferrite → γ-austenite phase transformation before γ → α phase transformation and (3) without Laves phase particles. CP particles were found to be effective in reducing the creep rates from the transient creep regime to the early stage of a slowly accelerating creep regime but were coarsened after the creep tests. IP particles were less effective in reducing the creep rate in the early creep stages but showed a higher stability against particle coarsening than CP particles in the creep tests, suggesting their effectiveness in delaying the recovery and recrystallization processes in the matrix and thereby retarding the onset of a rapid creep acceleration and creep rupture. The effects of the different precipitation routes are discussed based on the results obtained. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

25 pages, 10203 KiB  
Article
On Attempting to Create a Virtual Laboratory for Application-Oriented Microstructural Optimization of Multi-Phase Materials
by Faisal Qayyum, Sergey Guk, Rudolf Kawalla and Ulrich Prahl
Appl. Sci. 2021, 11(4), 1506; https://0-doi-org.brum.beds.ac.uk/10.3390/app11041506 - 07 Feb 2021
Cited by 12 | Viewed by 2237
Abstract
Physics-based and phenomenological crystal plasticity numerical simulations provide an opportunity to develop microstructurally informed models for multi-phase material. The Düsseldorf Advanced Material Simulation Kit (DAMASK) has been developed as a flexible tool for modeling and studying the several deformation mechanisms of such materials [...] Read more.
Physics-based and phenomenological crystal plasticity numerical simulations provide an opportunity to develop microstructurally informed models for multi-phase material. The Düsseldorf Advanced Material Simulation Kit (DAMASK) has been developed as a flexible tool for modeling and studying the several deformation mechanisms of such materials at the microscopic and macroscopic scales. In the recent past, several methodologies and techniques were developed for obtaining or constructing microstructural details and calibrating the physics-based model parameters for single-phase and multi-phase materials. Combining and standardizing the devised methods with an appropriate database can help establish a virtual laboratory to analyze the effect of microstructural attributes on the mechanical behavior of multi-phase materials. This article deals with the comprehensive background of the developed techniques and methods for the multi-phase materials class by the current research group. The combinations of different experimental and numerical techniques to validate results are explained along with the advantages and limitations. The ideas of combining the different available tools and the associated challenges are discussed. The article presents some recent work related to the phase parameters identification of the multi-phase materials and detailed insight into the obtained results. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

16 pages, 6824 KiB  
Article
Parameter Identification for Thermo-Mechanical Constitutive Modeling to Describe Process-Induced Residual Stresses and Phase Transformations in Low-Carbon Steels
by Muhammed Zubair Shahul Hameed, Christoph Hubertus Wölfle, Tobias Robl, Thomas Obermayer, Stefan Rappl, Kai Osterminski, Christian Krempaszky and Ewald Werner
Appl. Sci. 2021, 11(2), 550; https://0-doi-org.brum.beds.ac.uk/10.3390/app11020550 - 08 Jan 2021
Cited by 5 | Viewed by 2441
Abstract
Reinforcing steel bars (rebars) are widely manufactured using the Tempcore™ process. Several studies have been conducted analyzing the effect of the heat treatment route on the strength and corrosion resistance of rebars, but knowledge of its effects on the residual stresses of the [...] Read more.
Reinforcing steel bars (rebars) are widely manufactured using the Tempcore™ process. Several studies have been conducted analyzing the effect of the heat treatment route on the strength and corrosion resistance of rebars, but knowledge of its effects on the residual stresses of the finished product are largely lacking. This paper presents experimental investigations to identify the material parameters necessary to simulate the Tempcore™ process using thermo-elasto-plastic constitutive modeling in order to study the generation of residual stresses during the manufacturing process. Mechanical parameters such as yield strength at elevated temperatures and elastic constants were determined experimentally. A continuous cooling transformation diagram needed to model the phase transformations was also identified and is presented here. Residual stress distributions in the surface region of the rebar were characterized using X-ray diffraction. Further characterizations of microstructure, chemical composition, and hardness were carried out. The constitutive modeling approach for the numerical simulation is briefly described for which the experimentally determined parameters are required as input. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

11 pages, 3057 KiB  
Article
Effect of Thermo-Mechanical Processing on the Corrosion Behavior of Fe−30Mn−5Al−0.5C TWIP Steel
by Ulises Martin, Jacob Ress, Juan Bosch and David M. Bastidas
Appl. Sci. 2020, 10(24), 9104; https://0-doi-org.brum.beds.ac.uk/10.3390/app10249104 - 19 Dec 2020
Cited by 7 | Viewed by 1798
Abstract
Electrochemical corrosion of thermo-mechanically processed (TMP) and recrystallized Fe−30Mn−5Al−0.5C twinning-induced plasticity (TWIP) steels containing 30 wt.% Mn was studied in a 1.0 wt.% NaCl electrolyte solution. The alkaline nature of the corrosion products containing manganese oxide (MnO) increases the dissolution kinetics of the [...] Read more.
Electrochemical corrosion of thermo-mechanically processed (TMP) and recrystallized Fe−30Mn−5Al−0.5C twinning-induced plasticity (TWIP) steels containing 30 wt.% Mn was studied in a 1.0 wt.% NaCl electrolyte solution. The alkaline nature of the corrosion products containing manganese oxide (MnO) increases the dissolution kinetics of the TWIP steel in acid media, obtaining Mn2+ cations in solution, and producing the hydrogen evolution reaction (HER). X-ray photoelectron spectroscopy (XPS) surface analysis revealed an increased Al2O3 content of 91% in the passive layer of the recrystallized TWIP steel specimen, while in contrast only a 43% Al2O3 was found on the TMP specimen. Additionally, the chemical composition of the surface oxide layer as well as the TWIP alloy microstructure was analyzed by optical microscopy (OM) and scanning electron microscopy (SEM). The results indicate an enhanced corrosion attack for the TMP high-Mn TWIP steel. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

13 pages, 5945 KiB  
Article
Analysis of the Thermomechanical Fatigue Behavior of Fully Ferritic High Chromium Steel Crofer®22 H with Cyclic Indentation Testing
by Bastian Blinn, David Görzen, Torsten Fischer, Bernd Kuhn and Tilmann Beck
Appl. Sci. 2020, 10(18), 6461; https://0-doi-org.brum.beds.ac.uk/10.3390/app10186461 - 16 Sep 2020
Cited by 9 | Viewed by 1951
Abstract
The 22 wt.% Cr, fully ferritic stainless steel Crofer®22 H has higher thermomechanical fatigue (TMF)- lifetime compared to advanced ferritic-martensitic P91, which is assumed to be caused by different damage tolerance, leading to differences in crack propagation and failure mechanisms. To [...] Read more.
The 22 wt.% Cr, fully ferritic stainless steel Crofer®22 H has higher thermomechanical fatigue (TMF)- lifetime compared to advanced ferritic-martensitic P91, which is assumed to be caused by different damage tolerance, leading to differences in crack propagation and failure mechanisms. To analyze this, instrumented cyclic indentation tests (CITs) were used because the material’s cyclic hardening potential—which strongly correlates with damage tolerance, can be determined by analyzing the deformation behavior in CITs. In the presented work, CITs were performed for both materials at specimens loaded for different numbers of TMF-cycles. These investigations show higher damage tolerance for Crofer®22 H and demonstrate changes in damage tolerance during TMF-loading for both materials, which correlates with the cyclic deformation behavior observed in TMF-tests. Furthermore, the results obtained at Crofer®22 H indicate an increase of damage tolerance in the second half of TMF-lifetime, which cannot be observed for P91. Moreover, CITs were performed at Crofer®22 H in the vicinity of a fatigue crack, enabling to locally analyze the damage tolerance. These CITs show differences between crack edges and the crack tip. Conclusively, the presented results demonstrate that CITs can be utilized to analyze TMF-induced changes in damage tolerance. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

15 pages, 6485 KiB  
Article
Impact of Thermomechanical Fatigue on Microstructure Evolution of a Ferritic-Martensitic 9 Cr and a Ferritic, Stainless 22 Cr Steel
by Bernd Kuhn, Jennifer Lopez Barrilao and Torsten Fischer
Appl. Sci. 2020, 10(18), 6338; https://0-doi-org.brum.beds.ac.uk/10.3390/app10186338 - 11 Sep 2020
Cited by 6 | Viewed by 2094
Abstract
The highly flexible operation schemes of future thermal energy conversion systems (concentrating solar power, heat storage and backup plants, power-2-X technologies) necessitate increased damage tolerance and durability of the applied structural materials under cyclic loading. Resistance to fatigue, especially thermomechanical fatigue and the [...] Read more.
The highly flexible operation schemes of future thermal energy conversion systems (concentrating solar power, heat storage and backup plants, power-2-X technologies) necessitate increased damage tolerance and durability of the applied structural materials under cyclic loading. Resistance to fatigue, especially thermomechanical fatigue and the associated implications for material selection, lifetime and its assessment, are issues not considered adequately by the power engineering materials community yet. This paper investigates the principal microstructural evolution, damage and failure of two steels in thermomechanical fatigue loading: Ferritic-martensitic grade 91 steel, a state of the art 9 wt % Cr power engineering grade and the 22 wt % Cr, ferritic, stainless Crofer® 22 H (trade name of VDM Metals GmbH, Germany; under license of Forschungszentrum Juelich GmbH) steel. While the ferritic-martensitic grade 91 steel suffers pronounced microstructural instability, the ferritic Crofer® 22 H provides superior microstructural stability and offers increased fatigue lifetime and more forgiving failure characteristics, because of innovative stabilization by (thermomechanically triggered) precipitation of fine Laves phase particles. The potential for further development of this mechanism of strengthening against fatigue is addressed. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

15 pages, 6081 KiB  
Article
Thermomechanically Induced Precipitation in High-Performance Ferritic (HiperFer) Stainless Steels
by Xiuru Fan, Bernd Kuhn, Jana Pöpperlová, Wolfgang Bleck and Ulrich Krupp
Appl. Sci. 2020, 10(16), 5713; https://0-doi-org.brum.beds.ac.uk/10.3390/app10165713 - 18 Aug 2020
Cited by 8 | Viewed by 2076
Abstract
Novel high-performance fully ferritic (HiperFer) stainless steels were developed to meet the demands of next-generation thermal power-conversion equipment and to feature a uniquely balanced combination of resistance to fatigue, creep, and corrosion. Typical conventional multistep processing and heat treatment were applied to achieve [...] Read more.
Novel high-performance fully ferritic (HiperFer) stainless steels were developed to meet the demands of next-generation thermal power-conversion equipment and to feature a uniquely balanced combination of resistance to fatigue, creep, and corrosion. Typical conventional multistep processing and heat treatment were applied to achieve optimized mechanical properties for this alloy. This paper outlines the feasibility of thermomechanical processing for goal-oriented alteration of the mechanical properties of this new type of steel, applying an economically more efficient approach. The impact of treatment parameter variation on alloy microstructure and the resulting mechanical properties were investigated in detail. Furthermore, initial optimization steps were undertaken. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

12 pages, 2260 KiB  
Article
Impact of Tungsten on Thermomechanically Induced Precipitation of Laves Phase in High Performance Ferritic (HiperFer) Stainless Steels
by Jana Pöpperlová, Xiuru Fan, Bernd Kuhn, Wolfgang Bleck and Ulrich Krupp
Appl. Sci. 2020, 10(13), 4472; https://0-doi-org.brum.beds.ac.uk/10.3390/app10134472 - 28 Jun 2020
Cited by 11 | Viewed by 1964
Abstract
High-chromium ferritic stainless steels strengthened by Laves phase precipitates were developed for a high-temperature application in steam power plants. The impact of tungsten content on the precipitation of the intermetallic Laves phase during the newly developed thermomechanical process route was investigated. Due to [...] Read more.
High-chromium ferritic stainless steels strengthened by Laves phase precipitates were developed for a high-temperature application in steam power plants. The impact of tungsten content on the precipitation of the intermetallic Laves phase during the newly developed thermomechanical process route was investigated. Due to rapid thermomechanically induced precipitation, a considerable reduction in processing time in comparison to the conventional solely thermal two-step processing of high chromium ferritic steels was achieved. Nevertheless, comparable mechanical properties at room temperature, i.e., the ultimate tensile strength of 712 MPa and the yield strength of 434 MPa, were obtained. The microstructure was analyzed by scanning electron microscopy (SEM) in combination with digital particle analysis, to estimate the particle size and the phase fraction of the Laves phase. The mean particle size of 52 nm and the volume fraction of 4.11% were achieved. Due to the tungsten content, an increase in the volume fraction and particle size was observed, giving rise to the higher strengthening effect. Full article
(This article belongs to the Special Issue Thermomechanical Properties of Steel)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-10
Back to TopTop