skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion

Abstract

Multi-step heat treatments comprise of high temperature forming (150 Degree-Sign C/24 h plus 190 Degree-Sign C for several minutes) and subsequent low temperature forming (120 Degree-Sign C for 24 h) is developed in creep age forming of 7075 aluminum alloy to decrease springback and exfoliation corrosion susceptibility without reduction in tensile properties. The results show that the multi-step heat treatment gives the low springback and the best combination of exfoliation corrosion resistance and tensile strength. The lower springback is attributed to the dislocation recovery and more stress relaxation at higher temperature. Transmission electron microscopy observations show that corrosion resistance is improved due to the enlargement in the size and the inter-particle distance of the grain boundaries precipitates. Furthermore, the achievement of the high strength is related to the uniform distribution of ultrafine {eta} Prime precipitates within grains. - Highlights: Black-Right-Pointing-Pointer Creep age forming developed for manufacturing of aircraft wing panels by aluminum alloy. Black-Right-Pointing-Pointer A good combination of properties with minimal springback is required in this component. Black-Right-Pointing-Pointer This requirement can be improved through the appropriate heat treatments. Black-Right-Pointing-Pointer Multi-step cycles developed in creep age forming of AA7075 for improving of springback and properties. Black-Right-Pointing-Pointer Results indicate simultaneous enhancing themore » properties and shape accuracy (lower springback).« less

Authors:
;  [1];  [1];  [1];  [2]
  1. Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)
  2. School of Materials Science and Engineering, MA University of Technology, P.O. Box 16765-3197, Tehran (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22163140
Resource Type:
Journal Article
Journal Name:
Materials Characterization
Additional Journal Information:
Journal Volume: 73; Journal Issue: Complete; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1044-5803
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ACCURACY; ALUMINIUM ALLOYS; CORROSION; CORROSION RESISTANCE; CREEP; DISLOCATIONS; GRAIN BOUNDARIES; HEAT TREATMENTS; PRECIPITATION; STRESS RELAXATION; TENSILE PROPERTIES; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Arabi Jeshvaghani, R., Zohdi, H., Shahverdi, H.R., E-mail: shahverdi@modares.ac.ir, Bozorg, M., and Hadavi, S.M.M. Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion. United States: N. p., 2012. Web. doi:10.1016/J.MATCHAR.2012.05.012.
Arabi Jeshvaghani, R., Zohdi, H., Shahverdi, H.R., E-mail: shahverdi@modares.ac.ir, Bozorg, M., & Hadavi, S.M.M. Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion. United States. doi:10.1016/J.MATCHAR.2012.05.012.
Arabi Jeshvaghani, R., Zohdi, H., Shahverdi, H.R., E-mail: shahverdi@modares.ac.ir, Bozorg, M., and Hadavi, S.M.M. Thu . "Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion". United States. doi:10.1016/J.MATCHAR.2012.05.012.
@article{osti_22163140,
title = {Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion},
author = {Arabi Jeshvaghani, R. and Zohdi, H. and Shahverdi, H.R., E-mail: shahverdi@modares.ac.ir and Bozorg, M. and Hadavi, S.M.M.},
abstractNote = {Multi-step heat treatments comprise of high temperature forming (150 Degree-Sign C/24 h plus 190 Degree-Sign C for several minutes) and subsequent low temperature forming (120 Degree-Sign C for 24 h) is developed in creep age forming of 7075 aluminum alloy to decrease springback and exfoliation corrosion susceptibility without reduction in tensile properties. The results show that the multi-step heat treatment gives the low springback and the best combination of exfoliation corrosion resistance and tensile strength. The lower springback is attributed to the dislocation recovery and more stress relaxation at higher temperature. Transmission electron microscopy observations show that corrosion resistance is improved due to the enlargement in the size and the inter-particle distance of the grain boundaries precipitates. Furthermore, the achievement of the high strength is related to the uniform distribution of ultrafine {eta} Prime precipitates within grains. - Highlights: Black-Right-Pointing-Pointer Creep age forming developed for manufacturing of aircraft wing panels by aluminum alloy. Black-Right-Pointing-Pointer A good combination of properties with minimal springback is required in this component. Black-Right-Pointing-Pointer This requirement can be improved through the appropriate heat treatments. Black-Right-Pointing-Pointer Multi-step cycles developed in creep age forming of AA7075 for improving of springback and properties. Black-Right-Pointing-Pointer Results indicate simultaneous enhancing the properties and shape accuracy (lower springback).},
doi = {10.1016/J.MATCHAR.2012.05.012},
journal = {Materials Characterization},
issn = {1044-5803},
number = Complete,
volume = 73,
place = {United States},
year = {2012},
month = {11}
}