Study of factors affecting Springback in Sheet Metal Forming and Deep Drawing Process

Deep drawing process is one of the important processes in sheet metal forming. One of the challenge that faces the deep drawing process is selecting the optimal values of process parameters for the deep drawing process. In order to find the optimum values of these parameters, it is necessary to study their influence on the deformation behaviour of the sheet metal. This paper develops a simulation model for deep drawing process based on Simufact sheet metal forming module to study the effect process parameters on the deep-drawing characteristics. The study also obtained the distribution of strain on the drawn product. Three process parameters are considered in this study namely, punch radius, die radius and clearance, the effect of these process parameter on the required force as well as on the quality of the product are investigated.

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Experimental investigation into a new hybrid-forming process: Incremental stretch drawing

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405416645983 ◽

2016 ◽

Vol 232 (3) ◽

pp. 475-486 ◽

Cited By ~ 8

Author(s):

Puneet Tandon ◽

Om Namah Sharma

Keyword(s):

Experimental Investigation ◽

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

Lead Time ◽

Drawing Process ◽

Forming Process ◽

Setup Cost ◽

Deep Drawing Process ◽

Incremental Sheet Metal Forming

Incremental sheet metal forming is an evolving process, which is suitable for the production of limited quantities of sheet metal components. The main advantages of this process over conventional forming processes are reduced setup cost and manufacturing lead time, as it eliminates the need of special purpose dies, improves formability, reduces forming forces, and provides process flexibility. The objective of this work is to investigate a new hybrid-forming process, which intends to combine incremental sheet metal forming with deep drawing process and has been named as “incremental stretch drawing.” A number of setups and fixtures were developed to carry out experiments to achieve incremental stretch drawing and understand the mechanism of the process. This process addresses some of the challenges of incremental sheet metal forming, that is, limited formability in terms of forming depth, especially at steeper wall angles and subsequent thinning of sheet. It is observed that the proposed process is able to reduce thinning as much as about 300%, considering same forming depth for incremental sheet metal forming and incremental stretch drawing processes. Improvement in formability, in terms of forming depths, also has been observed to be near about 100% in particular cases.

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Experimental Study of Drawing Load Curves in Forming Conical Parts by Hydroforming and Conventional Deep Drawing Processes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.556 ◽

2011 ◽

Vol 291-294 ◽

pp. 556-560 ◽

Cited By ~ 2

Author(s):

Salman Norouzi ◽

Amir Reza Yaghoubi ◽

Mohammad Bakhshi-Jooybari ◽

Abdolhamid Gorji

Keyword(s):

Experimental Study ◽

Sheet Metal Forming ◽

Deep Drawing ◽

Metal Forming ◽

Pure Copper ◽

Experimental Program ◽

Drawing Process ◽

Deep Drawing Process ◽

Load Variation ◽

Hydroforming Process

Since conical parts have wide applications in the industry and forming these parts is one of the most complex and difficult fields in sheet metal forming processes, the study on different methods in forming these parts can be useful. Hydroforming and conventional multistage deep drawing are two deep drawing processes which have been used to form conical parts. Hydroforming deep drawing is one of the special deep drawing processes which have been introduced in order to overcome some inherent problems in the conventional deep drawing with rigid tools. In the present work, an experimental program has been carried out to compare the drawing load variation and maximum drawing load in forming pure copper conical-cylindrical cups with the thickness of 2.5 mm by hydroforming and conventional multistage deep drawing processes. The results of the study demonstrate that drawing load variation is more uniform in the forming of conical parts by hydroforming deep drawing process. The maximum drawing load for drawing copper blank occurs at a higher amount in hydroforming process.

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Study on Loading Path Influences on the Thickness Distribution of TRIP Steels During Sheet Metal Forming

ASME 2009 International Manufacturing Science and Engineering Conference, Volume 1 ◽

10.1115/msec2009-84018 ◽

2009 ◽

Author(s):

W. J. Dan ◽

W. G. Zhang ◽

S. H. Li

Keyword(s):

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

Martensite Transformation ◽

Strain State ◽

Thickness Distribution ◽

Loading Path ◽

Drawing Process ◽

Deep Drawing Process ◽

Forming Temperature

Loading path is one of key factors that influence the formability of sheet metal forming processes. In this study, the effect of several kinds of loading paths on the thickness distribution of TRIP steel is investigated in a deep drawing process based on a constitutive model accompanying the strain-induced martensite transformation. A kinetic model of transformation, that describes the relationship between the thickness distribution of a deep drawing process and the martensite transformation, is used to calculate the martensite volume fraction. The influences of loading path on the martensite transformation are also evaluated through the change in the stress-strain state, the forming temperature, the transformation driving force, the nucleation site probability and the shear-band intersection controlled by the stress-strain state and forming temperature at the minimum thickness location in the formed part.

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Deep Drawing Process Design: A Multi Objective Optimization Approach

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.410-411.601 ◽

2009 ◽

Vol 410-411 ◽

pp. 601-608 ◽

Cited By ~ 1

Author(s):

Rosanna Di Lorenzo ◽

Giuseppe Ingarao ◽

Laura Marretta ◽

Fabrizio Micari

Keyword(s):

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

Optimal Solution ◽

Optimization Procedure ◽

Pareto Optimal Solution ◽

Pareto Optimal ◽

Drawing Process ◽

Deep Drawing Process ◽

Design Variables

In sheet metal forming most of the problems are multi objective problems, generally characterized by conflicting objectives. The definition of proper parameters aimed to prevent both wrinkles and fracture is a typical example of an optimization problem in sheet metal forming characterized by conflicting goals. What is more, nowadays, a great interest would be focused on the availability of a cluster of possible optimal solutions instead of a single one, particularly in an industrial environment. Thus, the design parameters calibration, accomplishing all the objectives, is difficult and sometimes unsuccessful. In order to overcome this drawback a multi-objectives optimization procedure based on Pareto optimal solution search techniques seems a very attractive approach to deal with sheet metal forming processes design. In this paper, an integration between numerical simulations, response surface methodology and Pareto optimal solution search techniques was applied in order to design a rectangular deep drawing process. In particular, the initial blank shape and the blank holder force history were optimized as design variables in order to accomplish two different objectives: reduce excessive thinning and avoid wrinkling occurrence. The steps of the optimization procedure include: 1) application of Central Composite Design (CCD) for the identification of the necessary data over the domain of variation of the design variables; 2) numerical simulations of the samples identified by CCD; 3) development of a response surface model to interpret the final objectives as functions of the design variables; 4) Pareto optimal solution analysis to reach the most performing design variables. The final aim is to develop a predictive tool able to identify a sort of process window for the analyzed process also minimizing the computational effort in particular with respect to mono-objective optimization techniques or traditional trial and error methods. Many possible technological scenarios were investigated by the implemented procedure and a set of reliable solutions, i.e. able to satisfy different design requirements, were obtained.

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Numerical Simulation in Deep Drawing of Cylindrical Cup with Circular Diving Equally Small Holes on Edge of Circle Blank

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.769 ◽

2010 ◽

Vol 148-149 ◽

pp. 769-773

Author(s):

Yu Qing Shi

Keyword(s):

Sheet Metal ◽

Deep Drawing ◽

Metal Forming ◽

Failure Modes ◽

Small Hole ◽

Drawing Process ◽

Deep Drawing Process ◽

Blank Shape ◽

Cylindrical Cup ◽

Small Holes

Deep-drawing is one of the most important methods to form sheet metal ,but wrinkling and fracture are the main failure modes in sheet-metal forming. Blank shape is important for deep-drawing because of an effective way to promote deep formability sheet metal .This paper presents an attempt to determine the effect of circle blank with circular diving equally small hole on edge of circle blank on the fracture and wrinkling and was investigated using 08Al sheet metal .The circular blank with small hole of diameter = was analyzed to eliminate wrinkling and fracture in deep-drawing .The aim of this study is to investigate the circular diving equally small hole on edge of circle blank on formability in the deep-drawing process and to obtain useful date from the industrial field .The experiment show that limit formability promote with punching small holes on circle blank in deep-drawing process.

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Numerical Simulation in Deep Drawing of Cylindrical Cup with Elliptical Shape Die Shoulder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1355 ◽

2010 ◽

Vol 148-149 ◽

pp. 1355-1359

Author(s):

Yu Qing Shi ◽

Ai Zhi Guan

Keyword(s):

Sheet Metal ◽

Deep Drawing ◽

Metal Forming ◽

Failure Modes ◽

Major Axis ◽

Minor Axis ◽

Drawing Process ◽

Deep Drawing Process ◽

Elliptical Shape ◽

Cylindrical Cup

Wrinkling and tearing are the main failure modes in sheet-metal forming. The radius of die is important for deep-drawing because of an effective way to promote deep formability sheet metal .This paper presents an attempt to determine the effect of various elliptical shape die shoulder on the fracture and wrinkling and was investigated using 08Al sheet metal .The ellipse with minor axis of b=4.5mm and major axis of a=6.5mm,a=7mm,a=8mm ,a=10mm were analyzed to eliminate wrinkling and fracture in deep-drawing .The aim of this study is to investigate the effect of elliptical major axis and elliptical minor axis variables in elliptical shape die shoulder on formability in the deep-drawing process and to obtain useful date from the industrial field .The experiment show that limit formability promote with elliptical shape die shoulder in deep-drawing process.

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New Approach for Wrinkle Prediction in Deep Drawing Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.639.459 ◽

2015 ◽

Vol 639 ◽

pp. 459-466

Author(s):

Fei Han ◽

Ranko Radonjic

Keyword(s):

Sheet Metal Forming ◽

Deep Drawing ◽

Metal Forming ◽

Optical Measurement ◽

Thin Sheet ◽

Drawing Process ◽

New Approach ◽

Deep Drawing Process ◽

Forming Technology ◽

Buckling Test

Due to the extensive use of thin sheet metals to reduce weight of car bodies, wrinkling is becoming a more common and one of the most undesirable defects in sheet metal forming processes. Recent experiments at the Institute for Metal Forming Technology (IFU), University of Stuttgart, indicated that the buckling test using modified specimens can enhance accuracy for the predication of wrinkling [1]. In this paper a new method to predict the onset of the wrinkling will be introduced, and results of this test will be compared with real deep drawing parts. The wrinkle heights will be considered an evaluated regarding to results obtained by an optical measurement system.

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Multi-Step Forward Finite Element Method for the Numerical Simulation of Sheet Metal Forming

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.474-476.251 ◽

2011 ◽

Vol 474-476 ◽

pp. 251-254

Author(s):

Jian Jun Wu ◽

Wei Liu ◽

Yu Jing Zhao

Keyword(s):

Numerical Simulation ◽

Finite Element Method ◽

Finite Element ◽

Sheet Metal ◽

Sheet Metal Forming ◽

Deep Drawing ◽

Metal Forming ◽

Mapping Method ◽

Constitutive Relationship ◽

Element Method

The multi-step forward finite element method is presented for the numerical simulation of multi-step sheet metal forming. The traditional constitutive relationship is modified according to the multi-step forming processes, and double spreading plane based mapping method is used to obtain the initial solutions of the intermediate configurations. To verify the multi-step forward FEM, the two-step simulation of a stepped box deep-drawing part is carried out as it is in the experiment. The comparison with the results of the incremental FEM and test shows that the multi-step forward FEM is efficient for the numerical simulation of multi-step sheet metal forming processes.

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