Special Issue "Metal Forming and Forging"

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Manufacturing Processes and Systems".

Deadline for manuscript submissions: 20 April 2022.

Special Issue Editors

Dr. Lander Galdós
E-Mail Website
Guest Editor
Department of Mechanical and Industrial Production, Mondragon Unibertsitatea, Loramendi 4, 20500 Mondragon, Spain
Interests: sheet metal forming; forging; material and tribological characterization; modelling
Prof. Dr. Daniel Casellas
E-Mail Website
Guest Editor
1. Eurecat, Centre Tecnològic de Catalunya, Manresa (Barcelona), Spain
2. Division of Mechanics of Solid Materials, Luleå University of Technology, Luleå, Sweden
Interests: fracture mechanics; fatigue; advanced high strength steels
Special Issues and Collections in MDPI journals

Special Issue Information

Dear Colleagues,

Metal forming and forging and are used extensively for the industrial production of high-added-value components using different metal alloys. Continuous research in both production techniques is necessary to understand the mechanisms that govern the transformation of the metal into its final shape, avoid final defects, and predict the final properties of the components.

The aim of this Special Issue is to collect outstanding papers about the above-mentioned processes that can help to solve and understand real industrial problems for better and more robust process design, process monitoring, and control.

Of special interest will be the contributions about the development of new material and the tribological/contact characterization methods ending in advanced numerical models that enable the simulation of complex industrial processes and their understanding. Linked to this, we are also expecting contributions about innovative processes that allow the manufacturing of complex components using conventional and hard to process metals. These new processes could be based on numerical modelling or experimental observations.

Dr. Lander Galdós
Prof. Daniel Casellas
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 papers will be 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. Materials 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 2000 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

  • Sheet metal forming: deep drawing and stamping, hot stamping and press hardening, gas or fluid media forming, shear forming, roll forming, and levelling
  • Bulk metal forming, forging: cold and hot forging, rolling processes, and bulk sheet metal forming
  • Material and tribological/contact characterization and modelling
  • Microstructural evolution modelling
  • Damagen failure and ductile fracture modelling, final properties prediction
  • Model-based process control, analytical and empirical methods

Published Papers (6 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Article
A Generalized Stress State and Temperature Dependent Damage Indicator Framework for Ductile Failure Prediction in Heat-Assisted Forming Operations
Materials 2021, 14(17), 5106; https://doi.org/10.3390/ma14175106 - 06 Sep 2021
Viewed by 333
Abstract
Heat-assisted forming processes are becoming increasingly important in the manufacturing of sheet metal parts for body-in-white applications. However, the non-isothermal nature of these processes leads to challenges in evaluating the forming limits, since established methods such as Forming Limit Curves (FLCs) only allow [...] Read more.
Heat-assisted forming processes are becoming increasingly important in the manufacturing of sheet metal parts for body-in-white applications. However, the non-isothermal nature of these processes leads to challenges in evaluating the forming limits, since established methods such as Forming Limit Curves (FLCs) only allow the assessment of critical forming strains for steady temperatures. For this reason, a temperature-dependent extension of the well-established GISSMO (Generalized Incremental Stress State Dependent Damage Model) fracture indicator framework is developed by the authors to predict forming failures under non-isothermal conditions. In this paper, a general approach to combine several isothermal FLCs within the temperature-extended GISSMO model into a temperature-dependent forming limit surface is investigated. The general capabilities of the model are tested in a coupled thermo-mechanical FEA using the example of warm forming of an AA5182-O sheet metal cross-die cup. The obtained results are then compared with state of the art of evaluation methods. By taking the strain and temperature path into account, GISSMO predicts greater drawing depths by up to 20% than established methods. In this way the forming and so the lightweight potential of sheet metal parts can by fully exploited. Moreover, the risk and locus of failure can be evaluated directly on the part geometry by a contour plot. An additional advantage of the GISSMO model is the applicability for low triaxialities as well as the possibility to predict the materials behavior beyond necking up to ductile fracture. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Article
Analysis of Deformation, the Stressed State and Fracture Predictions for Cogging Shafts with Convex Anvils
Materials 2021, 14(11), 3113; https://doi.org/10.3390/ma14113113 - 06 Jun 2021
Viewed by 564
Abstract
In this article, a new manner of cogging a forging (type: shaft), consisting in the application of a two-stage process composed of preliminary shaping in convex anvils, and also principal forging in flat or shaped anvils, is presented. A new manner of forging [...] Read more.
In this article, a new manner of cogging a forging (type: shaft), consisting in the application of a two-stage process composed of preliminary shaping in convex anvils, and also principal forging in flat or shaped anvils, is presented. A new manner of forging brought about the formation of favorable conditions for achieving the maximum values of the effective strain in the central part of a forging, accompanied by a simultaneous absence of tensile stresses, which was exerting a favorable influence upon reforging the axial zone of an ingot. What was determined, was the effective geometric shapes of convex anvils; the efficiency of different technological parameters in the case of the intensity of reforging the axial zone of an ingot was analyzed as well. The investigations were complemented by means of predicting the formation of ductile fractures in the course of forging with the application of three different ductile fracture criteria. The comparison of theoretical and experimental outcomes of investigations indicates a good level of being commensurate. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Article
Free-Forging of Pure Titanium with High Reduction of Thickness by Plasma-Carburized SKD11 Dies
Materials 2021, 14(10), 2536; https://doi.org/10.3390/ma14102536 - 13 May 2021
Viewed by 376
Abstract
A tool steel type SKD11 punch was plasma carburized at 673 K for 14.4 ks at 70 Pa to make carbon supersaturation. This carburized SKD11 punch was employed for upsetting the pure titanium wire with the diameter of 1.00 mm up to the [...] Read more.
A tool steel type SKD11 punch was plasma carburized at 673 K for 14.4 ks at 70 Pa to make carbon supersaturation. This carburized SKD11 punch was employed for upsetting the pure titanium wire with the diameter of 1.00 mm up to the reduction of thickness by 70% in a single shot. Its contact interface to titanium work was analyzed to describe the anti-galling behavior in this forging. Little trace of titanium proved that the galling process was suppressed by the in situ solid lubrication. The isolated free carbon agglomerates are wrought as a solid lubricant to sustain the galling-free forging process. This anti-galling upsetting reduced the residual strains in the forged wires. A long titanium wire with a length of 45 mm was incrementally upset to yield the titanium ribbon with a thickness of 0.3 mm, the width of 2.3 mm, and the length of 50 mm. The grain size of original pure titanium was much reduced to 2 μm on average. A micro-pillared microtexture was imprinted onto this forged titanium ribbon. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Article
Numerical Investigations on Thermal Forming Limit Testing with Local Inductive Heating for Hot Forming of AA7075
Materials 2021, 14(8), 1882; https://doi.org/10.3390/ma14081882 - 09 Apr 2021
Viewed by 549
Abstract
Forming 7000-series aluminum alloys under elevated temperatures is particularly attractive due to their increased formability. To enable process design by finite element simulation for hot forming, strain-based criteria, such as temperature-dependent forming limit diagrams (TFLD), can be consulted to assess forming feasibility. This [...] Read more.
Forming 7000-series aluminum alloys under elevated temperatures is particularly attractive due to their increased formability. To enable process design by finite element simulation for hot forming, strain-based criteria, such as temperature-dependent forming limit diagrams (TFLD), can be consulted to assess forming feasibility. This work numerically investigates the extent to which in-plane experimental concepts with partial inductive heating are suitable for detecting discrete failure points in TFLD. In particular, an alternative to the currently widely used thickness-reduced specimen geometries was created for cruciform specimens under biaxial tension. First, the temperature-dependent and strain-rate-dependent flow behavior was investigated for AA7075 under uniaxial tension. A heat source model for partial inductive heating was inversely parameterized based on heating experiments. Subsequently, the test procedures were simulated with different specimen geometries under discrete strain conditions. Different concepts were discussed for deriving a suitable specimen shape for the biaxial tension case, and the influence of different notch and slot forms were shown. The simulations showed that partial inductive heating was suitable to induce failure situations, thus creating TFLDs. For the biaxial tension case, a sufficiently large temperature gradient was required to use cruciform specimens without thickness reduction. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Article
An Analytical Model for Estimating the Bending Curvatures of Metal Sheets in Laser Peen Forming
Materials 2021, 14(2), 462; https://doi.org/10.3390/ma14020462 - 19 Jan 2021
Viewed by 623
Abstract
Laser peen forming (LPF) is suitable for shaping sheet metals without the requirement for die/mold and without causing high temperatures. An analytical model for estimating the bending curvatures of LPF is convenient and necessary for better understanding of the physical processes involved. In [...] Read more.
Laser peen forming (LPF) is suitable for shaping sheet metals without the requirement for die/mold and without causing high temperatures. An analytical model for estimating the bending curvatures of LPF is convenient and necessary for better understanding of the physical processes involved. In this paper, we describe a new analytical model based on internal force balance and the energy transformation in LPF. Experiments on 2024 aluminum alloy sheets of 1–3 mm thickness were performed to validate the analytical model. The results showed that for 1 mm and 3 mm thick–thin plates, the curvature obtained by the analytical model changes from −14 × 10−4 mm−1 and −1 × 10−4 mm−1 to 55 × 10−4 mm−1 and −21 × 10−4 mm−1, respectively, with the increase of laser energy, which is consistent with the experimental trend. So, when either the stress gradient mechanism (SGM) or the shock bending mechanism (SBM) overwhelmingly dominated the forming process, the analytical model could give relatively accurate predicted curvatures compared with the experimental data. Under those conditions where SGM and SBM were comparable, the accuracy of the model was low, because of the complex stress distributions within the material, and the complex energy coupling process under these conditions. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Article
Reconfigurable Multipoint Forming Using Waffle-Type Elastic Cushion and Variable Loading Profile
Materials 2020, 13(20), 4506; https://doi.org/10.3390/ma13204506 - 12 Oct 2020
Viewed by 701
Abstract
There is an increasing demand for flexible, relatively inexpensive manufacturing techniques that can accommodate frequent changes to part design and production technologies, especially when limited batch sizes are required. Reconfigurable multi-point forming (MPF) is an advanced manufacturing technique which uses a reconfigurable die [...] Read more.
There is an increasing demand for flexible, relatively inexpensive manufacturing techniques that can accommodate frequent changes to part design and production technologies, especially when limited batch sizes are required. Reconfigurable multi-point forming (MPF) is an advanced manufacturing technique which uses a reconfigurable die consisting of a set of moveable pins to shape sheet metal parts easily. This study investigates the use of a novel variable thickness waffle-type elastic cushion and a variable punch-loading profile to either eliminate or minimise defects associated with MPF, namely wrinkling, thickness variation, shape deviation, and dimpling. Finite element modelling (FEM), analysis of variance (ANOVA), and the response surface methodology (RSM) were used to investigate the effect of process parameters pertaining to the cushion dimensions and type of loading profile on the aforementioned defects. The results of this study indicate that the most significant process parameters were maximum cushion thickness, cushion cut-out base radius, and cushion cut-out profile radius. The type of loading profile was found to be insignificant in all responses, but further investigation is required as the rate, and the thermal effects were not considered in the material modelling. Optimal process parameters were found to be a maximum cushion thickness of 3.01 mm, cushion cut-out base radius of 2.37 mm, cushion cut-out profile radius of 10 mm, and a “linear” loading profile. This yielded 0.50 mm, 0.00515 mm, 0.425 mm for peak shape deviation, thickness variation, and wrinkling, respectively. Full article
(This article belongs to the Special Issue Metal Forming and Forging)
Show Figures

Figure 1

Back to TopTop