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Publications (10 of 141) Show all publications
Pérez Caro, L., Schill, M., Haller, K., Odenberger, E.-L. & Oldenburg, M. (2019). Damage and fracture during sheet-metal forming of alloy 718. International Journal of Material Forming
Open this publication in new window or tab >>Damage and fracture during sheet-metal forming of alloy 718
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2019 (English)In: International Journal of Material Forming, ISSN 1960-6206, E-ISSN 1960-6214Article in journal (Refereed) Epub ahead of print
Abstract [en]

Forming nickel-based superalloy aero-engine components is a challenging process, largely because of the risk of high degree of springback and issues with formability. In the forming tests conducted on alloy 718 at room temperature, open fractures are observed in the drawbead regions, which are not predicted while evaluating the formability using the traditional forming-limit diagram(FLD). This highlights the importance of an accurate prediction of failure during forming as, in some cases, may severely influence the springback and thereby the accuracy of the predicted shape distortions, leading the final shape of the formed component out of tolerance. In this study, the generalised incremental stress-state dependent damage model (GISSMO) is coupled with the isotropic von Mises and the anisotropic Barlat Yld2000-2D yield criteria to predict the material failure in the forming simulations conducted on alloy 718 using LS-DYNA. Their effect on the predicted effective plastic strains and shape deviations is discussed. The failure and instability strains needed to calibrate the GISSMO are directly obtained from digital image correlation (DIC) measurements in four different specimen geometries i.e. tensile, plane strain, shear, and biaxial. The damage distribution over the drawbeads is measured using a non-linear acoustic technique for validation purposes. The numerical simulations accurately predict failure at the same regions as those observed in the experimental forming tests. The expected distribution of the damage over the drawbeads is in accordance with the experimental measurements. The results highlight the potential of considering DIC to calibrate the GISSMO in combination with an anisotropic material model for forming simulations in alloy 718.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
alloy 718, damage, fracture, GISSMO, non-linear acoustic technique, optimisation
National Category
Metallurgy and Metallic Materials Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-62903 (URN)10.1007/s12289-018-01461-4 (DOI)
Projects
Virtuell processkedja för plåtformade flygmotorstrukturer i superlegeringar – Validering och demonstrator
Funder
VINNOVA, 2013-01173
Available from: 2017-04-05 Created: 2017-04-05 Last updated: 2019-02-13
Odenberger, E.-L., Pederson, R. & Oldenburg, M. (2019). Finite element modeling and validation of springback and stress relaxation in the thermo-mechanical forming of thin Ti-6Al-4V sheets. The International Journal of Advanced Manufacturing Technology
Open this publication in new window or tab >>Finite element modeling and validation of springback and stress relaxation in the thermo-mechanical forming of thin Ti-6Al-4V sheets
2019 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015Article in journal (Refereed) Epub ahead of print
Abstract [en]

In this work, a hot forming procedure is developed using computer-aided engineering (CAE) to produce thin Ti-6Al-4V sheet components in an effective way. Traditional forming methods involve time- and cost-consuming furnace heating and subsequent hot sizing steps. A material model for finite element (FE) analyses of sheet metal forming and springback at elevated temperatures in Ti-6Al-4V is calibrated and evaluated. The anisotropic yield criterion proposed by Barlat et al. 2003 is applied, and the time- and temperature-dependent stress relaxation behavior for elastic and inelastic straining are modeled using a Zener–Wert–Avrami formulation. Thermo-mechanical uniaxial tensile tests, a biaxial test, and uniaxial stress relaxation tests are performed and used as experimental reference to identify material model parameters at temperatures up to 700 °C. The hot forming tool setup is manufactured and used to produce double-curved aero engine components at 700 °C with different cycle times for validation purposes. Correlations between the predicted and measured responses such as springback and shape deviation show promising agreement, also when the forming and subsequent holding time was as low as 150 s. The short cycle time resulted in elimination of a detectable alpha case layer. Also, the tool surface coating extends the tool life in combination with a suitable lubricant. 

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Hot forming, Stress relaxation, Springback, Ti-6Al-4V, Plastic anisotropy, FE analysis
National Category
Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-75356 (URN)10.1007/s00170-019-04071-9 (DOI)
Available from: 2019-07-24 Created: 2019-07-24 Last updated: 2019-07-24
Deng, L., Pelcastre, L., Hardell, J., Prakash, B. & Oldenburg, M. (2019). Numerical investigation of galling in a press hardening experiment with AlSi-coated workpieces. Engineering Failure Analysis, 99, 85-96
Open this publication in new window or tab >>Numerical investigation of galling in a press hardening experiment with AlSi-coated workpieces
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2019 (English)In: Engineering Failure Analysis, ISSN 1350-6307, E-ISSN 1873-1961, Vol. 99, p. 85-96Article in journal (Refereed) Published
Abstract [en]

Press hardened steels are commonly used as a lightweight choice for manufacturing car components because of the high ratio of strength to weight. The use of ultra-high-strength steels for the design of lightweight vehicles contributes to the reduction of emissions of carbon dioxide while maintaining passenger safety. Stamping tools used in press hardening processes suffer harsh contact conditionsin terms of dramatic temperature changes, cyclic loadings, and complex interactions between coatings and oxidation. In mass production, tool wear is an inevitable problem that increases maintenance costs. Severe adhesive wear, also called galling, substantially occurs in the stamping tool used against Al—Si-coated workpieces. The galling that takes place during press hardening not only degrades the production quality but also shortens the service life of the tool. In order to properly arrange tool maintenance and minimize galling through adjusting process parameters, engineers need to know when and where galling occurs, based on modelling of the galling in press hardening simulations. In order to implement a galling simulation for press hardening, a modified Archard wear model is employed in the present study, which is a contact-mechanics-based model. The specific wear rate in the model is calibrated by the quantitative galling measurements of a high-temperature tribometer test. The tribological test is designed to mimic the press hardening conditions, where the correlations between galling and process parameters such as temperature, pressure, and sliding distance are outlined. The galling simulation is implemented in a full-scale press hardening experiment, and the predicted galling is validated in terms of severe galling positions and galling profiles. The galling profile evolution is correlated to variations in the contact conditions. Uncertainties in the numerical model, such as the choice of penalty scaling factor and friction coefficient, are analysed with a parameter study and discussed. This study demonstrates finite element (FE) simulations involving galling prediction in press hardening so as to improve product development and production efficiency.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Contact conditions, High-temperature tribometer, FE simulation, Galling prediction
National Category
Applied Mechanics Tribology (Interacting Surfaces including Friction, Lubrication and Wear)
Research subject
Solid Mechanics; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-73044 (URN)10.1016/j.engfailanal.2019.01.059 (DOI)000464957800008 ()2-s2.0-85061604416 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-02-27 (johcin)

Available from: 2019-02-27 Created: 2019-02-27 Last updated: 2019-05-02Bibliographically approved
Deng, L., Pelcastre, L., Hardell, J., Prakash, B. & Oldenburg, M. (2018). Experimental Evaluation of Galling Under Press Hardening Conditions. Tribology letters, 66(3), Article ID 93.
Open this publication in new window or tab >>Experimental Evaluation of Galling Under Press Hardening Conditions
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2018 (English)In: Tribology letters, ISSN 1023-8883, E-ISSN 1573-2711, Vol. 66, no 3, article id 93Article in journal (Refereed) Published
Abstract [en]

Severe adhesion, also referred to as galling, is a critical problem in press hardening, especially in stamping tools used for hot forming of Al–Si-coated ultra-high strength steel. Galling is known to develop rapidly on the tool surface and it negatively affects the quality of the formed products. Earlier research on this topic has focused on the galling initiation. However, studies on the galling development during extended sliding and the corresponding quantitative measurement still lack depth. In the present study, a tribological test is established to study the galling development under press hardening conditions. The tribological test set-up aims to simulate extended sliding between the Al–Si-coated boron steels and the tool die material. The contact conditions in the interface are studied by a numerical model of the tribological test. The friction coefficients and material transfer are discussed taking into account the variation of the different test conditions. Using the results from the tribological tests, the galling simulation is performed in the numerical model. A geometry-updated sample based on the galling (transferred material build-up) height is simulated and the consequent pressure fluctuation is obtained in the numerical model. This contributes to the explanation of the severe transferred material accumulation during the test.

Place, publisher, year, edition, pages
Springer, 2018
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Applied Mechanics
Research subject
Machine Elements; Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-69943 (URN)10.1007/s11249-018-1023-0 (DOI)000436540000001 ()2-s2.0-85049356784 (Scopus ID)
Note

Validerad;2018;Nivå 2;2018-06-27 (andbra)

Available from: 2018-06-27 Created: 2018-06-27 Last updated: 2018-07-23Bibliographically approved
Marth, S., Golling, S., Östlund, R. & Oldenburg, M. (2018). From Blank to Fractured Component: Numerical and Experimental Results of a Laboratory Scale Component. In: : . Paper presented at International Deep Drawing Research Group 37th Annual Conference 3–7 June 2018, University of Waterloo, Waterloo, Ontario, Canada. Institute of Physics (IOP), 418, Article ID 012008.
Open this publication in new window or tab >>From Blank to Fractured Component: Numerical and Experimental Results of a Laboratory Scale Component
2018 (English)Conference paper, Published paper (Refereed)
Abstract [en]

Hot stamping of boron alloyed steel has become a standard in the automotive industry for safety relevant chassis components. Hot stamping of ultra-high strength steel allows the design of complex geometries with superior mechanical properties. In the present work, a laboratory scale test component is followed up from blank to fractured component. The production process starts with a pre-cut blank, which then is austenitized, transferred to the press hardening tool, formed and quenched and ends with post-cooling to room temperature. These components are tested under tensile deformation until fracture, where force, elongation and the strain field on the components surface are measured. The strain field measurements are performed by using digital image correlation (DIC). The laboratory scale test component is evaluated using finite element modelling. The production process is modelled starting with a pre-cut austenitized blank, subsequent transfer and forming operation, and ends with post-cooling. Furthermore, the deformation and fracture under tension/bending is studied using the OPTUS damage model. The as-produced component is measured using a three dimensional scanning system. Shape deviation and thickness change are compared to in the forming simulation predicted geometry after post-cooling. A finite element investigation on the deformation and fracture under tensional/bending loading is conducted applying shape and thickness deviations in the model. The majority of industrial components undergo paint curing before they are included in an assembly. Paint baking is a heat treatment at relatively low temperatures and causes relaxation in a martensitic microstructure. The effect of paint baking on the mechanical response of the laboratory scale test component is investigated. In the present work the reliability of modelling tools from blank to fractured component is shown. The possibility is shown to predict the failure of the component, with the specific phase composition after the hot stamping process obtained from simulations. Furthermore, the influence of the paint baking process on the mechanical properties is presented.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2018
National Category
Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-71045 (URN)10.1088/1757-899X/418/1/012008 (DOI)2-s2.0-85054247283 (Scopus ID)
Conference
International Deep Drawing Research Group 37th Annual Conference 3–7 June 2018, University of Waterloo, Waterloo, Ontario, Canada
Available from: 2018-10-03 Created: 2018-10-03 Last updated: 2018-12-21Bibliographically approved
Odenberger, E.-L., Pérez Caro, L., Åhlin, H. & Oldenburg, M. (2018). Thermo-mechanical Material Characterization and Stretch-bend Forming of AA6016. Paper presented at International Deep Drawing Research Group 37th Annual Conference 3–7 June 2018, University of Waterloo, Waterloo, Ontario, Canada. IOP Conference Series: Materials Science and Engineering, 418, Article ID 012022.
Open this publication in new window or tab >>Thermo-mechanical Material Characterization and Stretch-bend Forming of AA6016
2018 (English)In: IOP Conference Series: Materials Science and Engineering, ISSN 1757-8981, E-ISSN 1757-899X, Vol. 418, article id 012022Article in journal (Refereed) Published
Abstract [en]

Lightweight design has become increasingly in focus for the manufacturing industry. Global environmental challenges, goals and legislations imply that lighter and sustainable products are imperative to remain competitive. One example is stamped products made of aluminum alloys which are of interest to the automotive industry, where lightweight designs are essential. In order to increase formability and to produce more complex geometries in stamped aluminum components there is a need to develop hot forming techniques. The Finite Element Method (FEM) has enabled important advances in the study and design of competitive manufacturing procedures for metal parts. Predicting the final geometry of a component is a complex task, especially if the forming procedure occurs at elevated temperatures. This work presents selected results from thermo-mechanical material testing procedures, FE-analyses and forming validation tests in AA6016 material. The material tests are used to determine the thermo-mechanical anisotropic properties, strain rate sensitivity and formability (Forming Limit Curves, FLC) at temperatures up to 490°C. Stretch-bending tests are performed to compare predicted results with experimental observations such as punch force, strain levels, thinning, forming temperatures, springback and failure. It was found that the heat-treatment and forming at elevated temperatures substantially increased formability and that measured responses could in general be predicted if care was taken to model the initial blank temperatures, heat transfer and thermo-mechanical material properties. The room temperature case confirms the importance of considering anisotropy.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2018
National Category
Applied Mechanics Other Civil Engineering
Research subject
Solid Mechanics; Mining and Rock Engineering
Identifiers
urn:nbn:se:ltu:diva-71364 (URN)10.1088/1757-899X/418/1/012022 (DOI)2-s2.0-85054260019 (Scopus ID)
Conference
International Deep Drawing Research Group 37th Annual Conference 3–7 June 2018, University of Waterloo, Waterloo, Ontario, Canada
Note

Konferensartikel i tidskrift;2018-10-30 (svasva)

Available from: 2018-10-30 Created: 2018-10-30 Last updated: 2019-01-11Bibliographically approved
Mozgovoy, S., Hardell, J., Deng, L., Oldenburg, M. & Prakash, B. (2018). Tribological Behavior of Tool Steel under Press Hardening Conditions Using Simulative Tests. Journal of tribology, 140(1), Article ID 011606.
Open this publication in new window or tab >>Tribological Behavior of Tool Steel under Press Hardening Conditions Using Simulative Tests
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2018 (English)In: Journal of tribology, ISSN 0742-4787, E-ISSN 1528-8897, Vol. 140, no 1, article id 011606Article in journal (Refereed) Published
Abstract [en]

Press hardening is employed in the automotive industry to produce advanced high-strength steel components for safety and structural applications. This hot forming process depends on friction as it controls the deformation of the sheet. However, friction is also associated with wear of the forming tools. Tool wear is a critical issue when it comes to the dimensional accuracy of the produced components and it reduces the service life of the tool. It is therefore desirable to enhance the durability of the tools by studying the influence of high contact pressures, cyclic thermal loading, and repetitive mechanical loading on tool wear. This is difficult to achieve in conventional tribological testing devices. Therefore, the tribological behavior of tool-workpiece material pairs at elevated temperatures was studied in a newly developed experimental setup simulating the conditions prevalent during interaction of the hot sheet with the tool surface. Uncoated 22MnB5 steel and aluminum-silicon (Al-Si)-coated 22MnB5 steel were tested at 750 °C and 920 °C, respectively. It was found that higher loads led to lower and more stable friction coefficients independent of sliding velocity or surface material. The influence of sliding velocity on the coefficient of friction was only marginal. In the case of Al-Si-coated 22MnB5, the friction coefficient was generally higher and unstable due to transfer of Al-Si coating material to the tool. Adhesion was the main wear mechanism in the case of uncoated 22MnB5

Place, publisher, year, edition, pages
The American Society of Mechanical Engineers (ASME), 2018
National Category
Applied Mechanics Tribology (Interacting Surfaces including Friction, Lubrication and Wear)
Research subject
Solid Mechanics; Machine Elements
Identifiers
urn:nbn:se:ltu:diva-65268 (URN)10.1115/1.4036924 (DOI)000415376300018 ()2-s2.0-85027285991 (Scopus ID)
Note

Validerad;2017;Nivå 2;2017-08-28 (andbra)

Available from: 2017-08-23 Created: 2017-08-23 Last updated: 2018-11-27Bibliographically approved
Golling, S., Östlund, R., Schill, M., Sjöblom, R., Mattiasson, K., Jergeus, J. & Oldenburg, M. (2017). A comparative study of different failure modeling strategies on a laboratory scale test component. In: Mats Oldenburg, Braham Prakash, Kurt Steinhoff (Ed.), 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings. Paper presented at 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017 (pp. 37-46). Warrendale, PA: Association for Iron & Steel Technology, AIST
Open this publication in new window or tab >>A comparative study of different failure modeling strategies on a laboratory scale test component
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2017 (English)In: 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings / [ed] Mats Oldenburg, Braham Prakash, Kurt Steinhoff, Warrendale, PA: Association for Iron & Steel Technology, AIST , 2017, p. 37-46Conference paper, Published paper (Refereed)
Abstract [en]

Ultra-high strength steel (UHSS) has become a common material in the automotive industry during the last decades. The technique of press hardening allows modifying and tailoring the material properties of the blank in accordance with desired performance.

In the present work, a laboratory scale test component is developed. On basis of tests on the component it is intended to investigate the deformation and fracture behavior of a boron alloyed steel after different heat treatments. The tooling is developed to allow the production of single phase microstructures like martensite and bainite as well as mixed microstructures containing ferrite. Testing of the component is performed in a standard tensile testing machine with additional digital speckle measurements to determine the strain to fracture in the critical cross section. The initial geometry shape introduces bending in the critical cross-section during tensile loading of the specimen.

The aim of this work is to compare different material models on a component like level, including the prediction of failure. A finite element model of a laboratory scale component is analyzed using LS-Dyna. To compare different failure modeling approaches a set of damage models is calibrated to full hardened, martensitic steel. The deformation and fracture behavior of the component is presented in terms of load-displacement, plastic strain-stress triaxiality as well as in principal strain space.

Place, publisher, year, edition, pages
Warrendale, PA: Association for Iron & Steel Technology, AIST, 2017
Series
CHS2-series ; 6
National Category
Other Mechanical Engineering Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-64049 (URN)978-1-935117-66-7 (ISBN)
Conference
6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017
Available from: 2017-06-15 Created: 2017-06-15 Last updated: 2017-11-24Bibliographically approved
Marth, S., Häggblad, H.-å. & Oldenburg, M. (2017). A comparison between Stepwise Modelling and Inverse Modelling methods for characterization of press hardened sheet metals. In: Mats Oldenburg, Braham Prakash, Kurt Steinhoff (Ed.), 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings. Paper presented at 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017 (pp. 281-288). Warrendale, PA: Association for Iron & Steel Technology, AIST
Open this publication in new window or tab >>A comparison between Stepwise Modelling and Inverse Modelling methods for characterization of press hardened sheet metals
2017 (English)In: 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings / [ed] Mats Oldenburg, Braham Prakash, Kurt Steinhoff, Warrendale, PA: Association for Iron & Steel Technology, AIST , 2017, p. 281-288Conference paper, Published paper (Refereed)
Abstract [en]

The demand for weight reduction of cars has increased the number of press hardened sheet metal parts used in the automotive industry. This leads to an increased demand on the precision of simulations of press hardened sheet metals. An accurate prediction of the post-necking behaviour of materials is therefore needed to increase the precision of computer simulations with large deformations, as for example in forming simulations and crash simulations. Especially fracture simulations of press hardened steel parts with tailored properties have a huge demand on precise material models.

Inverse modelling is a common engineering tool to characterize the elasto-plastic behaviour of materials.  Taking experimental data, such as force and displacement data, the material model parameters are optimised until the simulated output reaches a target function.  Then inverse modelling is highly time demanding and needs nonlinear hardening material models. 

Lately a new fast method for post necking characterisation of sheet metals, called the Stepwise Modelling Method (SMM), was presented. This method uses full field measurements to obtain the strain field on the surface of sheet metal tensile specimens.  Furthermore, the stepwise modelling method models an experimental hardening curve in a stepwise process.  This hardening curve is a piecewise linear curve and not restricted to any specific material model.

In this paper SMM is used to characterize the hardening behaviour for thermally treated boron steel.  These results are compared with the results of inverse modelling. Three different material models are used. The comparison shows a minor deviation in the resulting hardening relations between stepwise modelling and inverse modelling. Since the efficiency is an important factor in product development calculation times are taken into account.  Comparing calculation time using SMM is considerably more efficient than using inverse modelling. Furthermore another advantage of SMM is shown in the fact that the piecewise linear hardening curves can be fitted to almost any material model without computational costs.

Place, publisher, year, edition, pages
Warrendale, PA: Association for Iron & Steel Technology, AIST, 2017
Series
CHS2-series ; 6
Keywords
Stepwise modelling; Inverse modelling; Material characterisation; Boron steel; Press hardening; Material modelling
National Category
Manufacturing, Surface and Joining Technology Vehicle Engineering Metallurgy and Metallic Materials Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-62459 (URN)978-1-935117-66-7 (ISBN)
Conference
6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017
Available from: 2017-03-13 Created: 2017-03-13 Last updated: 2018-04-12Bibliographically approved
Casellas, D., Frómeta, D., Lara, T., Molas, S., Jonsén, P., Golling, S. & Oldenburg, M. (2017). A fracture mechanics approach to develop high crash resistant microstructures by press hardening. In: Mats Oldenburg, Braham Prakash, Kurt Steinhoff (Ed.), 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings. Paper presented at 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017 (pp. 101-107). Warrendale, PA: Association for Iron & Steel Technology, AIST
Open this publication in new window or tab >>A fracture mechanics approach to develop high crash resistant microstructures by press hardening
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2017 (English)In: 6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2: June 4-7 2017, Atlanta, Georgia, USA : proceedings / [ed] Mats Oldenburg, Braham Prakash, Kurt Steinhoff, Warrendale, PA: Association for Iron & Steel Technology, AIST , 2017, p. 101-107Conference paper, Published paper (Refereed)
Abstract [en]

Crashworthiness is a relevant engineering property for car parts. However it is not easy to measure at laboratory scale and complex impact tests have to be carried out to determine it. Crash resistance for high strength steel is commonly evaluated in terms of cracking pattern and energy absorption in crashed specimens. Accordingly, the material resistance to crack propagation, i.e. the fracture toughness, could be used to rank crashworthiness. It has been proved in a previous work by the authors, so the measure of fracture toughness, in the frame of fracture mechanics in small laboratory specimens, would allow determining the best microstructure for crash resistance parts. Press hardening offers the possibility to obtain a wide range of microstructural configurations, with different mechanical properties. So the aim of this work is to evaluate the fracture toughness following the essential work of fracture methodology for ferrite-pearlite, bainite, ferrite-bainite, martensite and martensite-bainite microstructures. Results showed that bainitic microstructures have high fracture toughness, similar to TWIP and CP steels, which allows pointing them as potential candidates for obtaining high crash resistance in parts manufactured by press hardening.

Place, publisher, year, edition, pages
Warrendale, PA: Association for Iron & Steel Technology, AIST, 2017
Series
CHS2-series ; 6
National Category
Other Mechanical Engineering Applied Mechanics
Research subject
Solid Mechanics
Identifiers
urn:nbn:se:ltu:diva-64054 (URN)978-1-935117-66-7 (ISBN)
Conference
6th International Conference Hot Sheet Metal Forming of High-Performance Steel CHS2, Atlanta, Georgia, 4-7 June 2017
Available from: 2017-06-15 Created: 2017-06-15 Last updated: 2017-11-24Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-7074-8960

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