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Title: Effects of thread interruptions on tool pins in friction stir welding of AA6061

Abstract

In this paper, effects of pin thread and thread interruptions (flats) on weld quality and process response parameters during friction stir welding (FSW) of 6061 aluminium alloy were quantified. Otherwise, identical smooth and threaded pins with zero to four flats were adopted for FSW. Weldability and process response variables were examined. Results showed that threads with flats significantly improved weld quality and reduced in-plane forces. A three-flat threaded pin led to production of defect-free welds under all examined welding conditions. Spectral analyses of in-plane forces and weld cross-sectional analysis were performed to establish correlation among pin flats, force dynamics and defect formation. Finally, the lowest in-plane force spectra amplitudes were consistently observed for defect-free welds.

Authors:
 [1];  [2];  [1]
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE; National Science Foundation (NSF)
Contributing Org.:
Univ. of South Carolina, Columbia, SC (United States)
OSTI Identifier:
1376495
Grant/Contract Number:
AC05-00OR22725; EEC-0437341
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Science and Technology of Welding and Joining
Additional Journal Information:
Journal Volume: 23; Journal Issue: 2; Journal ID: ISSN 1362-1718
Publisher:
Taylor & Francis
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; friction stir welding; unthreaded pin; threaded pin; flats; in-plane forces

Citation Formats

Reza-E-Rabby, Md., Tang, Wei, and Reynolds, Anthony P. Effects of thread interruptions on tool pins in friction stir welding of AA6061. United States: N. p., 2017. Web. doi:10.1080/13621718.2017.1341363.
Reza-E-Rabby, Md., Tang, Wei, & Reynolds, Anthony P. Effects of thread interruptions on tool pins in friction stir welding of AA6061. United States. doi:10.1080/13621718.2017.1341363.
Reza-E-Rabby, Md., Tang, Wei, and Reynolds, Anthony P. Wed . "Effects of thread interruptions on tool pins in friction stir welding of AA6061". United States. doi:10.1080/13621718.2017.1341363.
@article{osti_1376495,
title = {Effects of thread interruptions on tool pins in friction stir welding of AA6061},
author = {Reza-E-Rabby, Md. and Tang, Wei and Reynolds, Anthony P.},
abstractNote = {In this paper, effects of pin thread and thread interruptions (flats) on weld quality and process response parameters during friction stir welding (FSW) of 6061 aluminium alloy were quantified. Otherwise, identical smooth and threaded pins with zero to four flats were adopted for FSW. Weldability and process response variables were examined. Results showed that threads with flats significantly improved weld quality and reduced in-plane forces. A three-flat threaded pin led to production of defect-free welds under all examined welding conditions. Spectral analyses of in-plane forces and weld cross-sectional analysis were performed to establish correlation among pin flats, force dynamics and defect formation. Finally, the lowest in-plane force spectra amplitudes were consistently observed for defect-free welds.},
doi = {10.1080/13621718.2017.1341363},
journal = {Science and Technology of Welding and Joining},
number = 2,
volume = 23,
place = {United States},
year = {Wed Jun 21 00:00:00 EDT 2017},
month = {Wed Jun 21 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on June 21, 2018
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  • This paper reports on studies of the influences of various post-weld heat treatment procedures on tensile properties of friction stir-welded AA6061 aluminum alloy joints. Rolled plates of 6-mm thick AA6061 aluminum alloy were used to fabricate the joints. Solution treatment, an artificial aging treatment and a combination of both were given to the welded joints. Tensile properties such as yield strength, tensile strength, elongation and joint efficiency were evaluated. Microstructures of the welded joints were analyzed using optical microscopy and transmission electron microscopy. A simple artificial aging treatment was found to be more beneficial than other treatment methods to enhancemore » the tensile properties of the friction stir-welded AA6061 aluminum alloy joints.« less
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