Numerical and experimental evaluation of laser forming process for the shape correction in ultra high strength steels

2013 ◽  
Author(s):  
J. H. Song ◽  
J. Lee ◽  
S. Lee ◽  
E. Z. Kim ◽  
N. K. Lee ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
High Strength Steels ◽  
High Strength ◽  
Laser Forming ◽  
Forming Process ◽  
Shape Correction ◽  
Ultra High Strength Steels

Dissimilar Material Joint Strength and Structure for Friction Stir Forming Process

2014 ◽  
Author(s):  
Kenneth A. Ogata ◽  
Sladjan Lazarevic ◽  
Scott F. Miller
Keyword(s):  
Failure Modes ◽  
Dissimilar Materials ◽  
High Strength Steels ◽  
High Strength ◽  
Forming Process ◽  
Experimental Conditions ◽  
Friction Stir ◽  
Automotive Body ◽  
Neck Fracture ◽  
Ultra High Strength Steels

Mass reduction of automotive body structures is a critical part of achieving reduced CO2 emissions in the automotive industry. There has been significant work on the application of ultra high strength steels and aluminum alloys. However, the next paradigm is the integrated use of both materials, which creates the need to join them together. Friction stir forming is a new environmentally benign manufacturing process for joining dissimilar materials. The concept of this process is stir heating one material and forming it into a mechanical interlocking joint with the second material. In this research the process was experimentally analyzed in a computer numerical controlled machining center between aluminum and steel work pieces. The significant process parameters were identified and their optimized settings for the current experimental conditions defined using a design of experiments methodology. Three failure modes were identified (neck fracture, aluminum sheet peeling, and bonding delamination i.e. braze fracture). The overall joint structure and grain microstructure were mapped along different stages of the friction stir forming process. Two layers were formed within the aluminum, the thermo-mechanical affected zone that had been deformed due to the contact pressure and angular momentum of the tool, and the heat affected deformation zone that deformed into the cavity.

Testing and Modeling of Roll Levelling Process

2014 ◽  
Vol 611-612 ◽  
pp. 1753-1762 ◽  
Author(s):  
Elena Silvestre ◽  
Eneko Sáenz de Argandoña ◽  
Lander Galdos ◽  
Joseba Mendiguren
Keyword(s):  
Finite Element ◽  
High Strength Steels ◽  
Beam Theory ◽  
High Strength ◽  
Theoretical Models ◽  
Element Model ◽  
Forming Process ◽  
Element Analysis ◽  
Design Engineers ◽  
Ultra High Strength Steels

Roll levelling is a forming process used to remove the residual stresses and imperfections of metal strips by means of plastic deformations. During the process the metal fibres are subjected to cyclic tension-compression deformations leading to achieve flat product. The process is especially important to avoid final geometrical errors when coils are cold formed or when thick plates are cut by laser. In the last years, and due to the appearance of high strength materials such as Ultra High Strength Steels, machine design engineers are demanding a reliable tool for the dimensioning of the levelling facilities. In response to this demand, Finite Element Analysis and Analytical methods are becoming an important technique able to lead engineers towards facilities optimization through a deeper understanding of the process. Aiming to this study two different models have been developed to analyze the roll levelling operations: an analytical model and a finite element model. The FE-analysis was done using 2D-modelling assuming plane strain conditions. Differing settings, leveller configuration and materials were investigated. The one-dimensional analytical levelling model is based on classical beam theory to calculate the induced strain distribution through the strip, and hence the evolving elastic/plastic stress distribution. Both models provide a useful guide to process-sensitivities and are able to identify causes of poor leveller performance. The theoretical models have been verified by a levelling experimental prototype with 13 rolls at laboratory.

State of the Art: Prototyping of the Roll Bending Machine

2013 ◽  
Vol 549 ◽  
pp. 76-83
Author(s):  
Jarmo Mäkikangas ◽  
Kari Kutuniva ◽  
Kari Mäntyjärvi
Keyword(s):  
High Strength Steels ◽  
High Strength ◽  
Roll Forming ◽  
Modular Construction ◽  
Forming Process ◽  
Roll Bending ◽  
Short Run ◽  
New Type ◽  
Ultra High Strength Steels ◽  
Functional Components

This paper focuses on the development of a new type of roll bending machine. Our primary aim was to build a machine that could form ultra-high-strength steels (UHS) with smaller inner radii than those achieved by traditional bending methods. One of the main planning principles was modular construction, so a length of a bending line could be easily selected or changed later by the user without major changes to the basic construction of the machine. In contrast, in traditional roll forming, the blank does not move during the forming process, so the accuracy of the profile can be better controlled. Different kinds of cut to size-open profiles can be produced by this machine, which utilizes and combines bending and rolling techniques. In the initial stages of the project, the needs of smaller companies that do short-run productions are taken into account. First, the prototype is designed mainly for research use; moreover, it is important that the properties of the machine are multifunctional. In addition, forming can be done in several ways by this machine. In this paper, there is shown creation of a machine, designing of construction and manufacturing steps of the whole machine including assembling. Also detailed description of the various functional components and the operating principle is presented. The results of the forming tests are also presented.

Texture analysis and joint performance of laser-welded similar and dissimilar dual-phase and complex-phase ultra-high-strength steels

2021 ◽  
Vol 174 ◽  
pp. 111035
Author(s):  
Ajit Kumar Pramanick ◽  
Hrishikesh Das ◽  
Ji-Woo Lee ◽  
Yeyoung Jung ◽  
Hoon-Hwe Cho ◽  
...  
Keyword(s):  
Texture Analysis ◽  
High Strength Steels ◽  
High Strength ◽  
Dual Phase ◽  
Complex Phase ◽  
Joint Performance ◽  
Ultra High Strength Steels

Laser Forming for Flexible Fabrication

2000 ◽  
Vol 16 (02) ◽  
pp. 97-109
Author(s):  
Koichi Masubuchi ◽  
Jerry E. Jones
Keyword(s):  
Three Dimensional ◽  
Low Carbon Steel ◽  
High Strength Steels ◽  
Cost Benefit ◽  
Network Models ◽  
High Strength ◽  
Laser Forming ◽  
Low Carbon ◽  
Flat Plates ◽  
Neural Network Models

A 36-month program supported by the Defense Advanced Research Projects Agency (DARPA) was conducted to demonstrate the feasibility to predictably laser form a variety of ferrous and non-ferrous metals of different thickness. Laser forming provides a method of producing complex shapes in sheet, plate, and tubing without the use of tooling, molds, or dies. By heating a localized area with a laser beam, it is possible to create stress states that result in predictable deformation. This research program has developed, refined and demonstrated constitutive and empirical, and neural network models to predict deformation as a function of critical parametric variables and established an understanding of the effect of laser forming on some metallurgical properties of materials. The program was organized into two, time-phased tasks. The first task involved forming flat plates to one-dimensional (I -D) shapes, such as, hinge bends in various materials including low-carbon steel, high-strength steels, nickel-based super alloys, and aluminum alloys. The second task expanded the work conducted in the first task to investigate three-dimensional (3-D) configurations. The models were updated, 3-D specimens fabricated and evaluated, and cost benefit analyses were performed.

Characterization of a AISI/SAE 4340 Steel in Different Microstructural Conditions

2014 ◽  
Vol 775-776 ◽  
pp. 136-140 ◽  
Author(s):  
Renato Araujo Barros ◽  
Antonio Jorge Abdalla ◽  
Humberto Lopes Rodrigues ◽  
Marcelo dos Santos Pereira
Keyword(s):  
High Strength Steels ◽  
High Strength ◽  
Aviation Industry ◽  
Sodium Metabisulfite ◽  
Aerospace Applications ◽  
Aircraft Landing ◽  
Aircraft Landing Gear ◽  
Structural Applications ◽  
Ultra High Strength Steels ◽  
Pin On Disk

The 4340 are classified as ultra-high strength steels used by the aviation industry and aerospace applications such as aircraft landing gear and several structural applications, usually in quenched and tempered condition. In this situation occurs reduction of toughness, which encourages the study of multiphasic and bainític structures, in order to maintain strength without loss of toughness. In this study, ferritic-pearlitic structure was compared to bainitic and martensitic structure, identified by the reagents Nital, LePera and Sodium Metabisulfite. Sliding wear tests of the type pin-on-disk were realized and the results related to the microstructure of these materials and also to their hardnesses. It is noted that these different microstructures had very similar behavior, concluding that all three tested pairs can be used according to the request level.

scholarly journals Modeling of Forming Limit Bands for Strain-Based Failure-Analysis of Ultra-High-Strength Steels

Metals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 631 ◽  
Author(s):  
Hamid Bayat ◽  
Sayantan Sarkar ◽  
Bharath Anantharamaiah ◽  
Francesco Italiano ◽  
Aleksandar Bach ◽  
...  
Keyword(s):  
Material Properties ◽  
Driving Forces ◽  
Weight Ratio ◽  
High Strength Steels ◽  
High Strength ◽  
Forming Limit ◽  
Boron Steel ◽  
Passenger Safety ◽  
Ultra High Strength Steels ◽  
Increased Strength

Increased passenger safety and emission control are two of the main driving forces in the automotive industry for the development of light weight constructions. For increased strength to weight ratio, ultra-high-strength steels (UHSSs) are used in car body structures. Prediction of failure in such sheet metals is of high significance in the simulation of car crashes to avoid additional costs and fatalities. However, a disadvantage of this class of metals is a pronounced scatter in their material properties due to e.g., the manufacturing processes. In this work, a robust numerical model is developed in order to take the scatter into account in the prediction of the failure in manganese boron steel (22MnB5). To this end, the underlying material properties which determine the shapes of forming limit curves (FLCs) are obtained from experiments. A modified Marciniak–Kuczynski model is applied to determine the failure limits. By using a statistical approach, the material scatter is quantified in terms of two limiting hardening relations. Finally, the numerical solution obtained from simulations is verified experimentally. By generation of the so called forming limit bands (FLBs), the dispersion of limit strains is captured within the bounds of forming limits instead of a single FLC. In this way, the FLBs separate the whole region into safe, necking and failed zones.

Sign in / Sign up

Export Citation Format

Share Document