Joining dissimilar grade aluminum alloy sheets using multi-hole dieless friction stir riveting process
- PDF / 4,286,877 Bytes
- 18 Pages / 595.276 x 790.866 pts Page_size
- 25 Downloads / 183 Views
ORIGINAL ARTICLE
Joining dissimilar grade aluminum alloy sheets using multi-hole dieless friction stir riveting process Tinu P. Saju 1
&
R. Ganesh Narayanan 2 & Barnik Saha Roy 3
Received: 22 May 2020 / Accepted: 11 November 2020 # Springer-Verlag London Ltd., part of Springer Nature 2020
Abstract A recently developed spot joining process namely dieless friction stir riveting is explored for understanding the effect of multihole configurations on the joint formation in dissimilar grades of aluminum alloy sheets. These spot joints are strengthened by mechanical interlocking together with metallurgical bonding and possesses the absence of hook defect as well as pin hole defect. This contributes to superior lap shear fracture load than conventional spot joints. The mechanical load performance tests, detailed macro/micro structure analysis, the hardness measurement, external morphological study, and fracture mode analysis are conducted. Single-hole configuration yields appreciable mechanical performance than multi-hole configurations by achieving lap shear fracture load accounting about 7.42 kN and cross-tension fracture load accounting about 2.89 kN. The farther the holes in multi-hole configurations, the more imperfect the mechanical interlocking becomes. The dynamic recrystallization, associated grain growth, and its relation with the extent of plastic deformation in distinct zones of the joint are also identified. The frictional heat flux and severe plastic deformation have significantly affected the hardness of the two sheets. Critical weak zones leading to various fracture modes of the joint are also identified. Keywords Friction stir form joining . Friction stir spot welding . Dieless friction stir riveting . Microstructure . Aluminum alloy . Hardness
1 Introduction New light-weight sheet metals like alloys of aluminum and magnesium are introduced in automobile and aerospace industries to realize the advantages from body mass reduction, fuel economy, and stability. Joining similar grades and dissimilar grades of such sheet metals is a major challenge.
* Tinu P. Saju [email protected] R. Ganesh Narayanan [email protected] Barnik Saha Roy [email protected] 1
Department of Mechanical Engineering, TKM College of Engineering, Kollam, Kerala 691005, India
2
Department of Mechanical Engineering, Indian Institute of Technology, Guwahati, Assam 781039, India
3
Department of Mechanical Engineering, National Institute of Technology, Agartala, Tripura 799046, India
Fusion welding techniques and fastening techniques are slowly getting obsolete for these newly inducted sheet metals. However, many new alternative solid-state joining techniques such as self-pierce riveting and clinching are being proposed in literature [1, 2]. Friction stir spot welding (FSSW) marked its presence in the manufacturing industry since 2004 [3]. The process has been gaining attention as one of the best choice for spot welding the light-weight sheet metals. Several research has been conducted for better understanding of FSSW and its a
Data Loading...
