FE simulation of asymmetric creep-ageing behaviour of AA2050 and its application to creep age forming
File(s)
Author(s)
Type
Journal Article
Abstract
A finite element (FE) model has been developed and validated in this study for the first-time to simulate the asymmetric creep-ageing behaviour of an Al-Cu-Li alloy (AA2050) for creep age forming (CAF) applications. An implicit integration algorithm integrated with the Secant method was proposed to efficiently solve the creep-ageing constitutive model of AA2050 and a “maximum principal stress” technique was employed to characterise the asymmetric tension and compression creep behaviour for CAF FE simulation. The proposed algorithm has been implemented into the FE solver in PAM-STAMP via a user-defined subroutine and an implicit FE model has been developed for CAF of AA2050. The effectiveness of the developed FE model has been validated by four-point-bending creep-ageing experiments of AA2050 plates with different thicknesses. The springback behaviour of AA2050 plates after 18 h CAF with a doubly curved tool was then predicted using the validated FE model. The results show that springback levels of the CAFed plates decreased with increasing thickness. Significant springback was observed in all the CAFed AA2050 plates within elastic loading, for example, the 8 mm plate which was initially loaded to near yielding had a springback value of 87.1% after 18 h CAF at 155 °C. The implicit algorithm and the maximum principal stress technique can be employed for constitutive models for other alloys with asymmetric creep-ageing behaviour.
Date Issued
2018-05-01
Date Acceptance
2018-03-07
ISSN
0020-7403
Publisher
Elsevier
Start Page
228
End Page
240
Journal / Book Title
International Journal of Mechanical Sciences
Volume
140
Copyright Statement
© 2018 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Subjects
Science & Technology
Technology
Engineering, Mechanical
Mechanics
Engineering
Creep age forming
Finite element method
Implicit algorithm
Asymmetric creep-ageing
Constitutive model
Al-Cu-Li alloy
FINITE-ELEMENT MODEL
CONSTITUTIVE-EQUATIONS
HEAT-TREATMENT
SPRINGBACK
ALLOY
PLASTICITY
FORMULATIONS
DEFORMATION
COMPRESSION
AIRCRAFT
0910 Manufacturing Engineering
0905 Civil Engineering
0913 Mechanical Engineering
Mechanical Engineering & Transports
Publication Status
Published
Date Publish Online
2018-03-08