Experimental and numerical investigation of sheet metal hydroforming (flexforming) process

Download

index.pdf

Date

2007

Author

Hatipoğlu, Hasan Ali

Metadata

Show full item record

Item Usage Stats

152
views

199
downloads

Sheet metal hydroforming(flexforming) is a process generally used in the manufacturing of aerospace parts in which a rubber diaphragm forms the sheet on a die with the help pressurized fluid and by this aspect it is different from the conventional stamping process. Some defects occur in the parts that are manufactured by this method and they are not different from the general sheet metal forming defects. Wrinkling, tearing and springback are among those defects. Variety of parts makes difficult to encounter these defects arising the detailed investigation of this process. In this work, the flexforming process was modeled by finite element method in order to investigate the operation windows of the problem. Various two and three-dimensional models were established with and without diaphragm, using explicit and implicit approach for time integration and using solid and shell elements for the blank. Using the material Aluminum 2024-T3 alclad sheet alloy, three basic experiments were conducted: Bending of a straight flange specimen, bending of a contoured flange specimen and bulging of a circular specimen. By these experiments the effects of blank thickness, die bend radius and forming pressure have been investigated. Experimental results were compared with finite element results to verify the computational models. Then, three selected aerospace sheet parts were analyzed and success of the model in the real life applications is proved.

Subject Keywords

Mechanical Engineering.

URI

http://etd.lib.metu.edu.tr/upload/12608755/index.pdf
https://hdl.handle.net/11511/16747

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Analysis of welding parameters in gas metal arc welding by a welding robot Erener, Yavuz; Arıkan, Mehmet Ali Sahir; Department of Mechanical Engineering (2006) In Robotic Gas Metal Arc Welding process, the welding parameters controlled by the welder (travel speed of the welding torch, wire feed speed, current, voltage, wire diameter, etc.) should be considered to obtain a desired welding quality. To design an appropriate welding model for the used equipment, the effects of each parameter should be studied by carrying out an adequate number of experiments. The welding process is described by analyzing the experimental data to define the relationships between the we...
Analysis of roll-forging process Karacaovalı, Hakan; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2005) Roll-forging is a metal forming process and mainly used for preform forging of long parts prior to press or hammer forging in the industry. Variable cross sections through the length of billet can be obtained by roll-forging to acquire an adequate distribution of material to the next forging stages. In the design of process and dies used in roll-forging, there are some empirical techniques in literature. However these techniques only provide approximate reduction ratio and elongation during the process and ...
Experimental and numerical analysis of compression on a forging press Biçer, Gökhan; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2010) Forging is a metal forming process which involves non-linear deformations. Finite element and finite volume software programs are commonly used to simulate the process. In these simulations, material properties are required. However, stress-strain relations of the materials at some elevated temperatures are not available in the material libraries of the related software programs. In this study, the stress-strain curves have been obtained by applying the Cook and Larke Simple Compression Test to AISI 1045 st...
Investigation of wear behavior of aged and non-aged SiC-reinforced AlSi7Mg2 metal matrix composites in dry sliding conditions ÇELİK, YAHYA HIŞMAN; Demir, Mehmet Emin; KILIÇKAP, EROL; Kalkanlı, Ali (Springer Science and Business Media LLC, 2020-01-01) Metal matrix composites (MMCs) with their splendid mechanical properties have been specifically designed for use in fields such as aerospace and aviation. The presence of hard ceramic particles in MMC increases the hardness of the matrix product and decreases its coefficient of friction. Therefore, the wear resistance is improved. Moreover, the mechanical properties of these composite materials can be improved by applying heat treatments. In this study, AlSi7Mg2 MMCs with 15 wt% SiC reinforcement were produ...
Modeling of particle filled resin impregnation in compression resin transfer molding Şaş, Hatice Sinem; Erdal Erdoğmuş, Merve; Department of Mechanical Engineering (2010) Compression Resin Transfer Molding (CRTM) is an advanced liquid molding process for producing continuous fiber-reinforced composite parts in relatively large dimensions and with high fiber volume fractions. This thesis investigates this process for the purpose of producing continuous fiber reinforced composites with particle fillers. In many composites, fillers are used within the resin for various reasons such as cost reduction and improvement of properties. However, the presence of fillers in a process in...

Citation Formats

H. A. Hatipoğlu, “Experimental and numerical investigation of sheet metal hydroforming (flexforming) process,” M.S. - Master of Science, Middle East Technical University, 2007.