Forming limit diagram (FLD) is the most appropriate tool used to obtain the safe strain region in sheet metal forming industries. This FLD is based on limiting values of major and minor strains. This Limiting strain is the strain at the onset of fracture / necking in a sheet metal. It is influenced by the material / condition of the material, strain condition in geometrical features of a sheet metal. In this paper, square pattern – square holed, perforated commercial aluminium sheets are considered for the study. The limiting strain for the above perforated sheet metals is predicted using finite element analysis. It is found that the limiting strain is controlled by percentage of open area, ligament ratio and hole size.

Venkatachalam G

Mechanical

School of Mechanical Engineering

Chennai Campus

Narayanan S

Department of Manufacturing Engineering

Vellore Campus

Sathiya Narayanan C.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Advanced Materials Research

Forming Limit Diagram (FLD) is a resourceful tool to study the formability of sheet metals. Research on the formability of Perforated Sheet Metal is growing over the years as perforated sheet metal finds its applications in various fields. But finding FLD of perforated sheet metals is complex due to the presence of holes. Also, the hole size, shape and pattern, ligament ratio, thickness of the blank, percentage of open area influence the formability of a perforated sheet metal.In the present scenario, various simulation softwares have made the process of plotting FLD much easier, saving time and money. This paper is an attempt to predict the formability of mild steel perforated sheet metal through simulation software package LS Dyna. Also, Parametric analysis is performed to determine the influence of geometric parameters on the drawability of the perforated sheet metal.

Applied Mechanics and Materials

Investigations on Influence of Geometric Parameters in Drawing of Perforated Sheet Metals

As the study of formability of perforated sheet metals using conventional approach is exhaustive and time consuming, Finite Element Analysis is used to carry out the same. This paper attempts to study the effects of perforation parameters (viz. hole size, open area and thickness) on the formability of square hole Perforated Mild Steel Sheet Metal. Finite element analysis is done using commercial Finite Element Analysis software LS-DYNA. Parametric analysis is carried out to optimize process parameters using Taguchi’s L9 orthogonal array. From the results obtained through simulation, the analysis of variance (ANOVA) is carried out to determine which group has best condition for drawing and regression equation is obtained to know, how a single response variable (Major or Minor strain) is related to a variety of predictor variables (percentage open area, hole size and thickness) and the graphs are plotted between them using MINITAB software.

Study of Forming Behaviour of Square Hole Mild Steel Perforated Sheet Metal

Interest in electromagnetic forming of sheet metals for automotive applications has been growing in recent years, due to its potential to form aluminium and other low formability materials. Further, to achieve the aim of weight reduction, some components are made of perforated sheet metals. The aim of this paper is to study and analyse the two stage electromagnetic forming of perforated aluminium sheet metals with the help of Finite Element method. The Electromagnetic force on the sheet is calculated using Ansys Emag by changing the parameters in current density, gap between coil and sheet, the coil thickness. The force is calculated for nine combinations of the three parameters. Taguchi orthogonal array is used to find the best combination of parameters. Also optimization of parameters controlling the electromagnetic force is found out using ANOVA technique. The obtained force is applied on the sheet and the corresponding deformation of the sheet is obtained using Ansys Structural. © 2014 Published by Elsevier Ltd.

Fulltext

Procedia Engineering

A Two Stage Finite Element Analysis of Electromagnetic Forming of Perforated Aluminium Sheet Metals

One of the needs of modern sheet metal forming is reliable knowledge about the formability of a given material. In sheet metal forming formability is usually related to the ability to have high values of the strain until failure, where this failure can be local necking and/or fracture. This high values of strain is called limiting strain which is not only influenced by material but also by the geometric features of sheet material. In this work, influence of hole shape and the patterns in which holes are arranged on limiting strain, are studied using experimental and numerical techniques. Both experimental and numerical analysis reveals the same.

Influence of Hole Shape and Pattern on the Prediction of Limiting Strain for Perforated Commercial Pure Aluminium Sheets

Prediction of Limiting Strains for Square Pattern – Square Hole Perforated Commercial Pure Aluminium Sheets

Manufacturing Technology

Material Analysis of Nickel Superalloy for Military Technology

Computational Materials Science

Modelling of forming limit diagram of perforated commercial pure aluminium sheets using artificial neural network

Journal of Materials Processing Technology

Evaluation of sheet metal formability by tensile tests

Yield criterion for a perforated sheet with a uniform triangular pattern of round holes and a low ligament ratio

Journal	Advanced Materials Research
Publisher	Trans Tech Publications, Ltd.
ISSN	10226680
Open Access	No