scholarly journals Towards Fracture Prediction in Single Point Incremental Forming

2013 ◽  
Vol 554-557 ◽  
pp. 2355-2362 ◽  
Author(s):  
Carlos Felipe Guzmán ◽  
Anne Marie Habraken
Keyword(s):  
Stress State ◽  
Incremental Forming ◽  
Single Point ◽  
Shell Element ◽  
Single Point Incremental Forming ◽  
Damage Development ◽  
Lode Parameter ◽  
Damage Models ◽  
Preliminary Study ◽  
Rupture Mechanism

The stress state in metal forming processes usually implies low values of triaxiality. It is well known that damage models based only on triaxiality fails to capture the damage behavior properly, and recent articles have stressed the effect of the Lode parameter in describing damage. Moreover, in some process like incremental forming, the through thickness shear could dominate the rupture mechanism making the description, using solely the triaxiality, inaccurate. In this paper, a preliminary study of the stress state is carried over a near-to-failure single point incremental forming (SPIF) formed cone, through finite elements simulations using a newly developed solid-shell element. The results provide a basis for further studies into damage development in SPIF.

scholarly journals Interaction of Process Parameters, Forming Mechanisms, and Residual Stresses in Single Point Incremental Forming

Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 656 ◽  
Author(s):  
Fabian Maaß ◽  
Marlon Hahn ◽  
A. Erman Tekkaya
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Stress State ◽  
Residual Stresses ◽  
Process Parameters ◽  
Process Model ◽  
Incremental Forming ◽  
Single Point ◽  
Single Point Incremental Forming ◽  
Residual Stress State

The residual stress state of a sheet metal component manufactured by metal forming has a significant influence on the mechanical properties, and thus determines the time until the component fails, especially for dynamic loads. The origin of the resulting residual stress state of incrementally formed parts with regard to the forming mechanisms of shearing, bending, and the normal stress component is still under investigation. The relationship between the process parameters, the forming mechanisms, and the resulting residual stress state for a complex part geometry manufactured by single point incremental forming (SPIF) is presented in this publication. For this purpose, a validated numerical process model is used to analyze the influence of the step-down increment Δz for truncated cones on the characteristics of the forming mechanisms and the resulting residual stress state. For the first time the forming mechanisms are evaluated numerically on both sides of the formed component. A relationship between the process parameters, forming mechanisms, residual stresses, and the mechanical properties of an incrementally formed component is shown. Shearing-induced hardening is identified as a relevant influence on the residual stress state of cones.

scholarly journals Numerical-Experimental Study Regarding the Single Point Incremental Forming Process

2021 ◽  
Vol 343 ◽  
pp. 03008
Author(s):  
Nicolae Rosca ◽  
Mihaela Oleksik ◽  
Liviu Rosca
Keyword(s):  
Experimental Research ◽  
Incremental Forming ◽  
Single Point ◽  
Shell Element ◽  
Adaptive Mesh ◽  
Single Point Incremental Forming ◽  
The Finite Element Method ◽  
Forming Process ◽  
Fully Integrated ◽  
Spiral Trajectory

The present paper proposes a numerical-experimental comparative study on the single point incremental forming process. A DC04 steel sheet with a thickness of 0.6 mm was used for both the numerical simulation using the finite element method and the experimental research. The type of trajectory used was a spiral trajectory and the finished part obtained was a truncated cone-shaped part. The analysis program used for simulation was Ls-Dyna. The simulations were performed in several variants: with a fixed mesh and with an adaptive mesh, using two different element formulations: 25 (Belytschko-Tsay formulation with thickness stretch) and -16 (fully integrated shell element modified for higher accuracy) and two contact types: automatic surface to surface (ASTS) and forming one way surface to surface (FOSS). The results of the numerical analysis and of the experimental research were focused on determining the major strain, minor strain, thickness reduction and forces at the end of the single point incremental forming process, as well as determining the processing time.

Numerical Simulation of a Pyramid Steel Sheet Formed by Single Point Incremental Forming Using Solid-Shell Finite Elements

2013 ◽  
Vol 549 ◽  
pp. 180-188 ◽  
Author(s):  
Laurent Duchêne ◽  
Carlos Felipe Guzmán ◽  
Amar Kumar Behera ◽  
Joost R. Duflou ◽  
Anne Marie Habraken
Keyword(s):  
Finite Element ◽  
Incremental Forming ◽  
Single Point ◽  
Shell Element ◽  
Single Point Incremental Forming ◽  
Solid Shell ◽  
Element Mesh ◽  
Assumed Strain ◽  
Geometric Deviations ◽  
Assumed Natural Strain

Single Point Incremental Forming (SPIF) is an interesting manufacturing process due to its dieless nature and its increased formability compared to conventional forming processes. Nevertheless, the process suffers from large geometric deviations when compared to the original CAD profile. One particular example arises when analyzing a truncated two-slope pyramid [. In this paper, a finite element simulation of this geometry is carried out using a newly implemented solid-shell element [, which is based on the Enhanced Assumed Strain (EAS) and the Assumed Natural Strain (ANS) techniques. The model predicts the shape of the pyramid very well, correctly representing the springback and the through thickness shear (TTS). Besides, the effects of the finite element mesh refinement, the EAS and ANS techniques on the numerical prediction are presented. It is shown that the EAS modes included in the model have a significant influence on the accuracy of the results.

Improve the Micro-hardness of Single Point Incremental Forming Product Using Magnetic Abrasive Finishing

2020 ◽  
Vol 38 (8A) ◽  
pp. 1137-1142
Author(s):  
Baqer A. Ahmed ◽  
Saad K. Shather ◽  
Wisam K. Hamdan
Keyword(s):  
Vickers Hardness ◽  
Feed Rate ◽  
Incremental Forming ◽  
Single Point ◽  
Single Point Incremental Forming ◽  
Step Size ◽  
Coil Current ◽  
Magnetic Abrasive Finishing ◽  
Finishing Process ◽  
Abrasive Finishing

In this paper the Magnetic Abrasive Finishing (MAF) was utilized after Single Point Incremental Forming (SPIF) process as a combined finishing process. Firstly, the Single Point Incremental forming was form the truncated cone made from low carbon steel (1008-AISI) based on Z-level tool path then the magnetic abrasive finishing process was applied on the surface of the formed product. Box-Behnken design of experiment in Minitab 17 software was used in this study. The influences of different parameters (feed rate, machining step size, coil current and spindle speed) on change in Micro-Vickers hardness were studied. The maximum and minimum change in Micro-Vickers hardness that achieved from all the experiments were (40.4 and 1.1) respectively. The contribution percent of (feed rate, machining step size, coil current and spindle speed) were (7.1, 18.068, 17.376 and 37.894) % respectively. After MAF process all the micro surface cracks that generated on the workpiece surface was completely removed from the surface.

Multiobjective optimization of process variables in single-point incremental forming using grey relational analysis coupled with entropy weights

2021 ◽  
pp. 146442072110204
Author(s):  
Abdulmajeed Dabwan ◽  
Adham E Ragab ◽  
Mohamed A Saleh ◽  
Atef M Ghaleb ◽  
Mohamed Z Ramadan ◽  
...  
Keyword(s):  
Grey Relational Analysis ◽  
Incremental Forming ◽  
Single Point ◽  
Sheet Forming ◽  
Incremental Sheet Forming ◽  
Numerical Control ◽  
Single Point Incremental Forming ◽  
Process Variables ◽  
Relational Analysis ◽  
Grey Relational

Incremental sheet forming is a specific group of sheet forming methods that enable the manufacture of complex parts utilizing computer numerical control instead of specialized tools. It is an incredibly adaptable operation that involves minimal usage of sophisticated tools, dies, and forming presses. Besides its main application in the field of rapid prototyping, incremental sheet forming processes can be used for the manufacture of unique parts in small batches. The goal of this study is to broaden the knowledge of the deformation process in single-point incremental forming. This work studies the deformation behavior in single-point incremental forming by experimentally investigating the principal stresses, principal strains, and thinning of single-point incremental forming products. Conical-shaped components are fabricated using AA1050-H14 aluminum alloy at various combinations of fundamental variables. The factorial design is employed to plan the experimental study and analysis of variance is conducted to analyze the results. The grey relational analysis approach coupled with entropy weights is also implemented to identify optimum process variables for single-point incremental forming. The results show that the tool diameter has the greatest effect on the thinning of the SPIF product, followed by the sheet thickness, step size, and feed rate.

scholarly journals Characterisation of geometrical and physical properties of a stainless steel denture framework manufactured by single-point incremental forming

2021 ◽  
Vol 10 ◽  
pp. 605-623
Author(s):  
Mladomir Milutinović ◽  
Robert Lendjel ◽  
Sebastian Baloš ◽  
Danka Labus Zlatanović ◽  
Luka Sevšek ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Physical Properties ◽  
Incremental Forming ◽  
Single Point ◽  
Single Point Incremental Forming
Sign in / Sign up

Export Citation Format

Share Document