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Title: A New Method for Reducing Dimensional Variability of Extruded Hollow Sections

Abstract

Crash boxes are one recent application example of aluminum extrusions in the automotive industry. A crash box is typically made by welding an extruded tube (tower) to a foot plate at one end, providing the mounting features towards the rail tip of the vehicle. When using fully automated welding processes, the exterior dimensions of the tower have to be within a tolerance of typically +/- 0.25 mm in order to provide consistent weld properties. However, the extrusion process commonly introduces dimensional variations exceeding those required for good weld quality. In order to avoid costly hydro-forming processes, a new mechanical calibration process has been developed. This method represents a means to achieve sufficient dimensional accuracy of the crash box tower prior to welding. A prototype die was made to validate the calibration process using alloy AA6063 T4 extrusions. Tensile tests were performed in order to determine material parameters. The geometry of each tower was carefully measured before and after forming to determine the dimensional capability of the calibration process. Statistical methods were combined with FEA simulations and analytical methods to establish surrogate models and response surfaces. The results show that the calibration process is an effective method for improving the dimensionalmore » accuracy of crash box profiles, providing significant improvements in dimensional capability. It is concluded that the methodology has a high industrial potential.« less

Authors:
;  [1];  [2]
+ Show Author Affiliations
  1. Department of Engineering Design and Materials, Norwegian University of Science and Technology (NTNU), N-7491, Trondheim (Norway)
  2. Hydro Aluminium Structures Raufoss AS, P.O. Box 15, N-2831, Raufoss (Norway)
Publication Date:
OSTI Identifier:
21061784
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: 10.1063/1.2740937; (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; ACCURACY; ALUMINIUM; ALUMINIUM ALLOYS; COMPUTERIZED SIMULATION; EXTRUSION; FINITE ELEMENT METHOD; MATHEMATICAL MODELS; PLATES; SURFACES; TESTING; TOLERANCE; TUBES; WELDED JOINTS; WELDING

Citation Formats

Baringbing, Henry Ako, Welo, Torgeir, and Soevik, Odd Perry. A New Method for Reducing Dimensional Variability of Extruded Hollow Sections. United States: N. p., 2007. Web. doi:10.1063/1.2740937.
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Baringbing, Henry Ako, Welo, Torgeir, & Soevik, Odd Perry. A New Method for Reducing Dimensional Variability of Extruded Hollow Sections. United States. doi:10.1063/1.2740937.
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Baringbing, Henry Ako, Welo, Torgeir, and Soevik, Odd Perry. Thu . "A New Method for Reducing Dimensional Variability of Extruded Hollow Sections". United States. doi:10.1063/1.2740937.
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@article{osti_21061784,
title = {A New Method for Reducing Dimensional Variability of Extruded Hollow Sections},
author = {Baringbing, Henry Ako and Welo, Torgeir and Soevik, Odd Perry},
abstractNote = {Crash boxes are one recent application example of aluminum extrusions in the automotive industry. A crash box is typically made by welding an extruded tube (tower) to a foot plate at one end, providing the mounting features towards the rail tip of the vehicle. When using fully automated welding processes, the exterior dimensions of the tower have to be within a tolerance of typically +/- 0.25 mm in order to provide consistent weld properties. However, the extrusion process commonly introduces dimensional variations exceeding those required for good weld quality. In order to avoid costly hydro-forming processes, a new mechanical calibration process has been developed. This method represents a means to achieve sufficient dimensional accuracy of the crash box tower prior to welding. A prototype die was made to validate the calibration process using alloy AA6063 T4 extrusions. Tensile tests were performed in order to determine material parameters. The geometry of each tower was carefully measured before and after forming to determine the dimensional capability of the calibration process. Statistical methods were combined with FEA simulations and analytical methods to establish surrogate models and response surfaces. The results show that the calibration process is an effective method for improving the dimensional accuracy of crash box profiles, providing significant improvements in dimensional capability. It is concluded that the methodology has a high industrial potential.},
doi = {10.1063/1.2740937},
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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Journal Article:
DOI:  10.1063/1.2740937
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