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Title: Crashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-Fill Radii and End Feeding Levels

Abstract

The automotive industry, with an increasing demand to reduce vehicle weight through the adoption of lightweight materials, requires a search of efficient methods that suit these materials. One attractive concept is to use hydroforming of aluminium tubes. By using FE simulations, the process can be optimized to reduce the risk for failure while maintaining energy absorption and component integrity under crash conditions. It is important to capture the level of residual ductility after forming to allow proper design for crashworthiness. This paper presents numerical and experimental studies that have been carried out for high pressure hydroforming operations to study the influence of the tube corner radius, end feeding, material thinning, and work hardening in 76.2 mm diameter, 3 mm wall thickness AA5754 aluminium alloy tube. End feeding was used to increase the formability of the tubes. The influence of the end feed displacement versus tube forming pressure schedule was studied to optimize the forming process operation to reduce thinning. Validation of the numerical simulations was performed by comparison of the predicted strain distributions and thinning, with measured quantities. The effect of element formulation (thin shell versus solid elements) was also considered in the models.

Authors:
;  [1]; ;  [2];  [3]
  1. National Research Council of Canada, Aluminium Technology Centre, 501 University Blvd. East, Chicoutimi, Quebec, G7H 8C3 (Canada)
  2. University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada)
  3. General Motors Technical Center, 6250 Chicago Road, Warren, MI (United States)
Publication Date:
OSTI Identifier:
21061757
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 908; Journal Issue: 1; Conference: NUMIFORM 2007: 9. international conference on numerical methods in industrial forming processes, Porto (Portugal), 17-21 Jun 2007; Other Information: DOI: 10.1063/1.2740906; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM; ALUMINIUM ALLOYS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DESIGN; DISTRIBUTION; DUCTILITY; ENERGY ABSORPTION; FAILURES; FINITE ELEMENT METHOD; MATERIALS WORKING; OPTIMIZATION; SOLIDS; STRAIN HARDENING; STRAINS; THICKNESS; TUBES; VALIDATION

Citation Formats

D'Amours, Guillaume, Rahem, Ahmed, Williams, Bruce, Worswick, Michael, and Mayer, Robert. Crashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-Fill Radii and End Feeding Levels. United States: N. p., 2007. Web. doi:10.1063/1.2740906.
D'Amours, Guillaume, Rahem, Ahmed, Williams, Bruce, Worswick, Michael, & Mayer, Robert. Crashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-Fill Radii and End Feeding Levels. United States. doi:10.1063/1.2740906.
D'Amours, Guillaume, Rahem, Ahmed, Williams, Bruce, Worswick, Michael, and Mayer, Robert. Thu . "Crashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-Fill Radii and End Feeding Levels". United States. doi:10.1063/1.2740906.
@article{osti_21061757,
title = {Crashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-Fill Radii and End Feeding Levels},
author = {D'Amours, Guillaume and Rahem, Ahmed and Williams, Bruce and Worswick, Michael and Mayer, Robert},
abstractNote = {The automotive industry, with an increasing demand to reduce vehicle weight through the adoption of lightweight materials, requires a search of efficient methods that suit these materials. One attractive concept is to use hydroforming of aluminium tubes. By using FE simulations, the process can be optimized to reduce the risk for failure while maintaining energy absorption and component integrity under crash conditions. It is important to capture the level of residual ductility after forming to allow proper design for crashworthiness. This paper presents numerical and experimental studies that have been carried out for high pressure hydroforming operations to study the influence of the tube corner radius, end feeding, material thinning, and work hardening in 76.2 mm diameter, 3 mm wall thickness AA5754 aluminium alloy tube. End feeding was used to increase the formability of the tubes. The influence of the end feed displacement versus tube forming pressure schedule was studied to optimize the forming process operation to reduce thinning. Validation of the numerical simulations was performed by comparison of the predicted strain distributions and thinning, with measured quantities. The effect of element formulation (thin shell versus solid elements) was also considered in the models.},
doi = {10.1063/1.2740906},
journal = {AIP Conference Proceedings},
number = 1,
volume = 908,
place = {United States},
year = {Thu May 17 00:00:00 EDT 2007},
month = {Thu May 17 00:00:00 EDT 2007}
}
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