Next Article in Journal
Hybridization of Layered Iron Hydroxide Nanoclays and Conducting Polymer for Controlled Oxygen Scavenger
Next Article in Special Issue
Mechanical Property of Sn-58Bi Solder Paste Strengthened by Resin
Previous Article in Journal
Formation Control Algorithm of Multi-UAV-Based Network Infrastructure
Previous Article in Special Issue
Study on the Reliability of Sn50Pb49Sb1/Cu Solder Joints Subjected to γ-ray Irradiation
Article Menu
Issue 10 (October) cover image

Export Article

Open AccessArticle
Appl. Sci. 2018, 8(10), 1741;

Study on Microstructure and Fatigue Damage Mechanism of 6082 Aluminum Alloy T-Type Metal Inert Gas (MIG) Welded Joint

School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China
Shanghai Collaborative Innovation Center of Laser Advanced Manufacturing Technology, 333 Long Teng Road, Shanghai 201620, China
Author to whom correspondence should be addressed.
Received: 10 September 2018 / Revised: 19 September 2018 / Accepted: 20 September 2018 / Published: 27 September 2018
(This article belongs to the Special Issue Selected Papers from the NMJ2018)
PDF [9794 KB, uploaded 27 September 2018]


In this experiment, the T-joint of a 6082 aluminum alloy was welded by metal inert gas (MIG) welding and a fatigue test was carried out at room temperature. The mechanisms of generating pores and of fatigue fracture in welded joints are revealed in the case of incomplete penetration. There are two main types of pores: pores that are not welded and pores that are near the upper weld line of the weld. During welding, bubbles in the molten pool are adsorbed on the surface oxide film that is not penetrated, and cannot be floated to form pores; since it is a T-shaped welded joint, the molten pool is overhanged during welding, thereby forming pores near the fusion line. The fatigue strength of the welded joint based on the S–N curve at 107 cycles is estimated to be 37.6 MPa, which can reliably be predicted in engineering applications. Fatigue tests show that fatigue cracks are all generated in the pores of the incomplete penetration, and it and the pores form a long precrack, which leads to large stress concentration, and the fracture occurs under a small applied load. Grain morphology around the pores also has a large effect on the fatigue properties of the T-weld joint. In the weld’s fatigue fracture, it was found that the crack stable-extension zone exhibited ductile-fracture characteristics, and the instantaneous fault zone is composed of a large number of tear-type dimples showing ductile fractures. View Full-Text
Keywords: aluminum alloy; MIG; T-joint; pore; fatigue damage mechanism aluminum alloy; MIG; T-joint; pore; fatigue damage mechanism

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Duan, C.; Yang, S.; Gu, J.; Xiong, Q.; Wang, Y. Study on Microstructure and Fatigue Damage Mechanism of 6082 Aluminum Alloy T-Type Metal Inert Gas (MIG) Welded Joint. Appl. Sci. 2018, 8, 1741.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Appl. Sci. EISSN 2076-3417 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top