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
Heat Treatment of Iron- and Aluminum-Based Alloys
share announcement

Heat Treatment of Iron- and Aluminum-Based Alloys

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 2021) | Viewed by 21917

Special Issue Editor

Dr. Silvia Barella

E-Mail Website
Guest Editor
Department of Mechanics, Politecnico di Milano, Milan, Italy
Interests: metals; plastic defomation; heat treatment; stainless steel
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Heat treatments have been used by mankind since the primeval times of iron-making. Over the centuries, blacksmiths became aware of the increase in mechanical properties of the heat-treated art craft. However, the explanation of these phenomena only became clear at the end of the 19th century. Despite three thousand years of experience, the heat treatments of metals continue to be studied and improved. New alloys and production process developments are released in the need of new and more efficient heat treatments. Furthermore, cost reduction and environmental sustainability play a role in the development of innovative techniques in this field. In particular, the knowledge about the principles at the base of the hardening mechanisms are also fundamental to the insightful design of different heat treatments able to bring components to market more quickly. This Special Issue aims to present the latest research related to advanced treatment techniques for the new generation of iron-based (i.e., light steel, Q&P) and aluminum-based alloys, also related to innovative production processes such as additive manufacturing and semisolid casting. Research reports associated with the development of a sustainable system for the reduction in the use of polluting elements and increasing the energy efficiency of the heat treatments are also welcome.

Prof. Silvia Barella
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

  • Heat treatments
  • Steel
  • Aluminum
  • Thermo-chemical treatment
  • Quenching
  • Aging
  • Partitioning
  • Mechanical properties
  • Microstructure evolution
  • Modelling

Published Papers (7 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:

Editorial

Jump to: Research

2 pages, 166 KiB  
Editorial
Heat Treatment of Iron- and Aluminum-Based Alloys
by Silvia Barella
Metals 2023, 13(6), 1141; https://doi.org/10.3390/met13061141 - 19 Jun 2023
Viewed by 764
Abstract
Iron- and aluminum-based alloys are the most commonly used metallic materials for engineering applications [...] Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)

Research

Jump to: Editorial

14 pages, 5841 KiB  
Article
Transformation of the δ-Ferrite in SS2343 Austenitic Stainless Steel upon Annealing at 1050 °C, 1150 °C and 1250 °C
by Boštjan Arh, Franc Tehovnik and Franci Vode
Metals 2021, 11(6), 935; https://doi.org/10.3390/met11060935 - 09 Jun 2021
Cited by 7 | Viewed by 5970
Abstract
The solidification behaviors of laboratory cast austenitic SS2343 stainless steel in terms of the volume fraction of δ-ferrite in the as-cast state and its transformation after subsequent annealing were investigated. Monitoring of morphological transformations of δ-ferrite in the microstructure show the progress of [...] Read more.
The solidification behaviors of laboratory cast austenitic SS2343 stainless steel in terms of the volume fraction of δ-ferrite in the as-cast state and its transformation after subsequent annealing were investigated. Monitoring of morphological transformations of δ-ferrite in the microstructure show the progress of δ-ferrite dissolution. Annealing tests were conducted at 1050 °C, 1150 °C and 1250 °C with soaking times of 5 and 40 min. The thermodynamic prediction and metallographic identification of δ-ferrite are presented. The ferrite fractions were measured using a magnetic method and determined to be in the range between 10.7% and 14.6%. The volume share of δ-ferrite decreased with an increase in temperature and the time of annealing. About 50–55% the δ-ferrite was effectively transformed. The δ-ferrite phase, originally present in a dendritic morphology, tends to break up and spheroidize. The morphology varies from vermicular, lacy and acicular shapes to globular for higher temperatures and for longer exposure times. In the δ-ferrite after annealing, concentrations of Cr and Mo decrease, and conversely the concentration of Ni increase, all by small, but significant, amounts. The observed changes in the solute concentration can be explained in terms of the transformation of ferrite into austenite and sigma phases. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)
►▼ Show Figures

Figure 1

17 pages, 7241 KiB  
Article
Quantitative Research on the Effect of Natural Aging on the Mechanical Properties and Bake Hardening Properties of AA6014 Alloy within Six Months
by Zhengwei Gu, Yuting Han, Ziming Tang, Lingling Yi and Ge Yu
Metals 2021, 11(4), 673; https://doi.org/10.3390/met11040673 - 20 Apr 2021
Cited by 2 | Viewed by 2014
Abstract
This article is dedicated to quantitatively and systematically revealing the changes of mechanical properties and bake hardening properties of AA6014 alloy during six-month natural aging in detail. Three directions (0, 45, and 90° relative to the rolling direction) of the aluminum alloy sheets [...] Read more.
This article is dedicated to quantitatively and systematically revealing the changes of mechanical properties and bake hardening properties of AA6014 alloy during six-month natural aging in detail. Three directions (0, 45, and 90° relative to the rolling direction) of the aluminum alloy sheets and 16 time points within six months were selected to conduct experiments. The change trend of six mechanical properties (0.2% offset yield strength, ultimate tensile strength, plastic extension at maximum force, elongation after fracture, and strain hardening exponent) were obtained by a large number of micro-hardness measurements and tensile tests. The results show that elongations along the three directions are basically the same and do not drop significantly with the progress of natural aging but fluctuate within a certain range. The trends of the n value during natural aging before and after bake hardening are opposite and bake hardening leads to ~0.07 decrease of the n value. The PLC phenomenon disappears after 90 days of natural aging, and the yield strengths along the three directions also stabilize; thus, it can be inferred that the cluster changes tend to stabilize after 90 days natural aging. The large and systematic dataset are clearly and intuitively presented, which can not only be used to provide data reference for industrial production of automobile manufacturers but also be used to reveal the microscopic mechanism of the natural aging process. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)
►▼ Show Figures

Figure 1

19 pages, 5226 KiB  
Article
The Atmosphere’s Effect on Stainless Steel Slabs’ Oxide Formation in a CH4-Fuelled Reheating Furnace
by Aleksi Laukka, Eetu-Pekka Heikkinen and Timo Fabritius
Metals 2021, 11(4), 621; https://doi.org/10.3390/met11040621 - 12 Apr 2021
Cited by 5 | Viewed by 2560
Abstract
Utilising the oxyfuel practice for CH4-fuelled combustion has positive effects on the emissions, efficiency and cost of high temperature furnace practices. However, especially in older installations, oxyfuel usage requires retrofitting and alters the atmosphere in which the oxidation of the steel [...] Read more.
Utilising the oxyfuel practice for CH4-fuelled combustion has positive effects on the emissions, efficiency and cost of high temperature furnace practices. However, especially in older installations, oxyfuel usage requires retrofitting and alters the atmosphere in which the oxidation of the steel occurs, when compared to using air as the oxidiser. Stainless steel slab oxide growth during reheating was studied in different atmospheres. The simulated post-burn atmospheres from oxyfuel, lean oxyfuel and air-fuel practices were used to compare oxide-scale layer growth and morphology during simulated typical AISI 304 stainless steel slab reheating prior to hot rolling. Thermogravimetric measurements, glow discharge optical emission spectrometer (GDOES) and field-emission scanning electron microscope energy dispersive X-ray (FESEM-EDS) methodology were applied to discern differences between oxide growth and inner oxide layer morphology between the three practices. Switching from air to oxyfuel practice at a single temperature had the same increasing effect on the scale formation amount as a 25 °C temperature increase in air atmosphere. Inner oxide layer depth profiling revealed C, Si and Ni to be the main elements that differed between temperatures and atmospheres. A morphology study showed Si and Ni behaviour to be linked to breakaway oxidation. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)
►▼ Show Figures

Graphical abstract

11 pages, 2901 KiB  
Article
Effects of Wire Drawing and Annealing Conditions on Torsional Ductility of Cold Drawn and Annealed Hyper-Eutectoid Steel Wires
by Jin Young Jung, Kang Suk An, Pyeong Yeol Park and Won Jong Nam
Metals 2020, 10(8), 1043; https://doi.org/10.3390/met10081043 - 03 Aug 2020
Cited by 6 | Viewed by 4719
Abstract
The effects of microstructural features on torsional ductility of cold drawn and annealed hyper-eutectoid steel wires were investigated. The patented wire rods were successively dry drawn to ε = 0.79 (54.7%) ~ 2.38 (90.7%). To examine the effects of hot-dip galvanizing conditions on [...] Read more.
The effects of microstructural features on torsional ductility of cold drawn and annealed hyper-eutectoid steel wires were investigated. The patented wire rods were successively dry drawn to ε = 0.79 (54.7%) ~ 2.38 (90.7%). To examine the effects of hot-dip galvanizing conditions on torsional ductility, steel wires with ε = 1.95 were annealed at 500 °C for 30 s for ~1 h in a salt bath. In cold drawn wires, the number of turns to failure increased steadily, showing the maximum peak, and then decreased with drawing strain. During the post-deformation annealing at 500 °C, torsional ductility of steel wires decreased with annealing time, except for the rapid drop due to the occurrence of delamination for 10 s annealing. The decrease of the number of turns to failure would be attributed to the microstructural evolutions, accompanying the spheroidization and growth of cementite particles and the recovery of ferrite in cold drawn steel wires. From the relationship between microstructural evolution and torsional ductility, it was found that among microstructural features, the shape and orientation of lamellar cementite showed the significant effect on torsional ductility of cold drawn and annealed hyper-eutectoid steel wires. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)
►▼ Show Figures

Figure 1

12 pages, 7348 KiB  
Article
Investigation on Solid-State Phase Transformations in a 2510 Duplex Stainless Steel Grade
by Irene Calliari, Marco Breda, Claudio Gennari, Luca Pezzato, Massimo Pellizzari and Andrea Zambon
Metals 2020, 10(7), 967; https://doi.org/10.3390/met10070967 - 17 Jul 2020
Cited by 15 | Viewed by 2560
Abstract
Duplex and Super Duplex Stainless Steels are very prone to secondary phases formation related to ferrite decomposition at high temperatures. In the present paper the results on secondary phase precipitation in a 2510 Duplex Stainless Steel, heat-treated in the temperature range 850–1050 °C [...] Read more.
Duplex and Super Duplex Stainless Steels are very prone to secondary phases formation related to ferrite decomposition at high temperatures. In the present paper the results on secondary phase precipitation in a 2510 Duplex Stainless Steel, heat-treated in the temperature range 850–1050 °C for 3–30 min are presented. The precipitation starts at grain boundaries with a consistent ferrite transformation for very short times. The noses of the Time–Temperature–Precipitation (TTP) curves are at 1000 °C for σ-phase and at 900 °C for χ-phase, respectively. The precipitation sequence involves a partial transformation of χ into σ, as previously evidenced in 2205 and 2507 grades. Furthermore, the experimental data were compared to the results of Thermo-Calc calculations. Understanding and ability to predict phase stability in 2510 duplex stainless steel is a key factor to design optimal welding processes that avoid any secondary phase precipitation in the weld bead as well as in the heat-affected zone. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based Alloys)
►▼ Show Figures

Figure 1

11 pages, 2747 KiB  
Article
Influence of Different Soaking Times at 1050 °C on the UT Response Due to Microstructure Evolution of 2205 Duplex Stainless Steel
by Andrea Gruttadauria, Silvia Barella, Carlo Mapelli and Davide Mombelli
Metals 2020, 10(4), 503; https://doi.org/10.3390/met10040503 - 11 Apr 2020
Cited by 2 | Viewed by 2127
Abstract
Under standard conditions, DSS (duplex stainless steel) features differing amounts of ferrite and austenite, essentially depending on the thermal treatment performed. This study is focused on the ultrasonic tests (UTs) response of DSS 2205, as a function of the microstructure, in terms of [...] Read more.
Under standard conditions, DSS (duplex stainless steel) features differing amounts of ferrite and austenite, essentially depending on the thermal treatment performed. This study is focused on the ultrasonic tests (UTs) response of DSS 2205, as a function of the microstructure, in terms of austenite volume fraction and austenitic grains evolution owing to different soaking times at 1050 °C. UTs were carried out on several samples. The samples underwent varying thermal treatments characterized by a constant maintenance temperature with different soaking times that allowed for microstructure evolution and modification of the structural constituents’ fraction. The UTs have highlighted an attenuation trend with the response mainly dependent upon the wave scattering and energy absorption caused by the grain features. In particular, the peak of sound attenuation was shown to correspond with the microstructure, which featured a major amount of austenite (in terms of volume fraction and the grain dimensions) and the disappearance of austenitic precipitates within the ferritic matrix. In order to obtain less UT attenuation, without affecting the mechanical and corrosion properties, the soaking should last as little time as possible. Full article
(This article belongs to the Special Issue Heat Treatment of Iron- and Aluminum-Based 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 1-7
Back to TopTop