Microstructure and Mechanical Properties of Refill Friction Stir Spot-Welded Joints of 2A12Al and 7B04Al: Effects of Tool Size and Welding Parameters

Yisong Wang; Pengyang Li; Haitao Jiang; Kang Yang; Zhenhao Chen; Haijiao Chuai; Xiaoyan Wu; Qiang Meng; Lin Ma

doi:10.3390/ma17030716

Materials (Feb 2024)

Microstructure and Mechanical Properties of Refill Friction Stir Spot-Welded Joints of 2A12Al and 7B04Al: Effects of Tool Size and Welding Parameters

Yisong Wang,
Pengyang Li,
Haitao Jiang,
Kang Yang,
Zhenhao Chen,
Haijiao Chuai,
Xiaoyan Wu,
Qiang Meng,
Lin Ma

Affiliations

Yisong Wang: National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Pengyang Li: College of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136, China
Haitao Jiang: National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Kang Yang: College of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136, China
Zhenhao Chen: College of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136, China
Haijiao Chuai: College of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136, China
Xiaoyan Wu: National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Qiang Meng: AVIC Manufacturing Technology Institute, Beijing 100024, China
Lin Ma: College of Material Science and Engineering, Shenyang Aerospace University, Shenyang 110136, China

DOI: https://doi.org/10.3390/ma17030716
Journal volume & issue: Vol. 17, no. 3
p. 716

Abstract

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To solve problems in dissimilarly light metal joints, refilled friction stir spot welding (RFSSW) is proposed instead of resistance spot welding. However, rotation speed, dwell time, plunge depth, and the diameter of welding tools all have a great influence on joints, which brings great challenges in optimizing welding parameters to ensure their mechanical properties. In this study, the 1.5 mm thick 2A12Al and 2 mm thick 7B04Al lap joints were prepared by Taguchi orthogonal experiment design and RFSSW. The welding tool (shoulder) diameters were 5 mm and 7 mm, respectively. The macro/microstructures of the cross-section, the geometrical characteristics of the effective welding depth (EWD), the stir zone area (SZA), and the stir zone volume (SZV) were characterized. The shear strength and failure mode of the lap joint were analyzed using an optical microscope. It was found that EWD, SZA, and SZV had a good correlation with tensile–shear force. The optimal welding parameters of 5 mm diameter joints are 1500 rpm of rotation speed, 2.5 mm of plunge depth, and 0 s of dwell time, which for 7 mm joints are 1200 rpm, 1.5 mm, and 2 s. The tensile–shear force of 5 mm and 7 mm joints welded with these optical parameters was 4965 N and 5920 N, respectively. At the same time, the 5 mm diameter joints had better strength and strength stability.

Published in Materials

ISSN: 1996-1944 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Technology: Electrical engineering. Electronics. Nuclear engineering; Technology: Engineering (General). Civil engineering (General); Science: Natural history (General): Microscopy; Science: Physics: Descriptive and experimental mechanics
Website: http://www.mdpi.com/journal/materials/

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