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Title: Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments

Abstract

Previous studies have shown that the presence of a pulsed electrical current, applied during the deformation process of an aluminum specimen, can significantly improve the formability of the aluminum without heating the metal above its maximum operating temperature range. The research herein extends these findings by examining the effect of electrical pulsing on 5052 and 5083 Aluminum Alloys. Two different parameter sets were used while pulsing three different heat treatments (As Is, 398°C, and 510°C) for each of the two aluminum alloys. For this research, the electrical pulsing is applied to the aluminum while the specimens are deformed, without halting the deformation process (a manufacturing technique known as Electrically-Assisted Manufacturing). The analysis focuses on establishing the effect the electrical pulsing has on the aluminum alloy’s various heat treatments by examining the displacement of the material throughout the testing region of dogbone-shaped specimens. The results from this research show that pulsing significantly increases the maximum achievable elongation of the aluminum (when compared to baseline tests conducted without electrical pulsing). Another beneficial effect produced by electrical pulsing is that the engineering flow stress within the material is considerably reduced. The electrical pulses also cause the aluminum to deform non-uniformly, such that themore » material exhibits a diffuse neck where the minimum deformation occurs near the ends of the specimen (near the clamps) and the maximum deformation occurs near the center of the specimen (where fracture ultimately occurs). This diffuse necking effect is similar to what can be experienced during superplastic deformation. However, when comparing the presence of a diffuse neck in this research, electrical pulsing does not create as significant of a diffuse neck as superplastic deformation. Electrical pulsing has the potential to be more efficient than traditional methods of incremental forming since the deformation process is never interrupted. Overall, with the greater elongation and lower stress, the aluminum can be deformed quicker, easier, and to a greater extent than is currently possible.« less

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1000608
Report Number(s):
PNNL-SA-73588
VT0505000; TRN: US201101%%409
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Manufacturing Science and Engineering, 132(5):Article No. 051016; Journal Volume: 132; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; ALUMINIUM; DEFORMATION; ELONGATION; FLOW STRESS; FRACTURES; HEAT TREATMENTS; HEATING; MANUFACTURING; TESTING; al 5xxx; fuel cel; pulsed current; heat treatments

Citation Formats

Salandro, Wesley A., Jones, Joshua J., McNeal, Timothy A., Roth, John T., Hong, Sung Tae, and Smith, Mark T.. Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments. United States: N. p., 2010. Web. doi:10.1115/1.4002185.
Salandro, Wesley A., Jones, Joshua J., McNeal, Timothy A., Roth, John T., Hong, Sung Tae, & Smith, Mark T.. Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments. United States. doi:10.1115/1.4002185.
Salandro, Wesley A., Jones, Joshua J., McNeal, Timothy A., Roth, John T., Hong, Sung Tae, and Smith, Mark T.. Fri . "Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments". United States. doi:10.1115/1.4002185.
@article{osti_1000608,
title = {Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments},
author = {Salandro, Wesley A. and Jones, Joshua J. and McNeal, Timothy A. and Roth, John T. and Hong, Sung Tae and Smith, Mark T.},
abstractNote = {Previous studies have shown that the presence of a pulsed electrical current, applied during the deformation process of an aluminum specimen, can significantly improve the formability of the aluminum without heating the metal above its maximum operating temperature range. The research herein extends these findings by examining the effect of electrical pulsing on 5052 and 5083 Aluminum Alloys. Two different parameter sets were used while pulsing three different heat treatments (As Is, 398°C, and 510°C) for each of the two aluminum alloys. For this research, the electrical pulsing is applied to the aluminum while the specimens are deformed, without halting the deformation process (a manufacturing technique known as Electrically-Assisted Manufacturing). The analysis focuses on establishing the effect the electrical pulsing has on the aluminum alloy’s various heat treatments by examining the displacement of the material throughout the testing region of dogbone-shaped specimens. The results from this research show that pulsing significantly increases the maximum achievable elongation of the aluminum (when compared to baseline tests conducted without electrical pulsing). Another beneficial effect produced by electrical pulsing is that the engineering flow stress within the material is considerably reduced. The electrical pulses also cause the aluminum to deform non-uniformly, such that the material exhibits a diffuse neck where the minimum deformation occurs near the ends of the specimen (near the clamps) and the maximum deformation occurs near the center of the specimen (where fracture ultimately occurs). This diffuse necking effect is similar to what can be experienced during superplastic deformation. However, when comparing the presence of a diffuse neck in this research, electrical pulsing does not create as significant of a diffuse neck as superplastic deformation. Electrical pulsing has the potential to be more efficient than traditional methods of incremental forming since the deformation process is never interrupted. Overall, with the greater elongation and lower stress, the aluminum can be deformed quicker, easier, and to a greater extent than is currently possible.},
doi = {10.1115/1.4002185},
journal = {Journal of Manufacturing Science and Engineering, 132(5):Article No. 051016},
number = 5,
volume = 132,
place = {United States},
year = {Fri Oct 01 00:00:00 EDT 2010},
month = {Fri Oct 01 00:00:00 EDT 2010}
}
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