Friction Stir Spot Welding: A Review on Joint Macro- and Microstructure, Property, and Process Modelling

X W Yang,T Fu,W Y Li

doi:10.1155/2014/697170

X W Yang, T Fu + Show 1 more

Open Access

https://doi.org/10.1155/2014/697170

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Abstract

Friction stir spot welding (FSSW) is a very useful variant of the conventional friction stir welding (FSW), which shows great potential to be a replacement of single-point joining processes like resistance spot welding and riveting. There have been many reports and some industrial applications about FSSW. Based on the open literatures, the process features and variants, macro- and microstructural characteristics, and mechanical properties of the resultant joints and numerical simulations of the FSSW process were summarized. In addition, some applications of FSSW in aerospace, aviation, and automobile industries were also reviewed. Finally, the current problems and issues that existed in FSSW were indicated.

Highlights

Lightweight metals such as aluminium alloys are increasingly used, especially in aerospace and automotive industries, where weight saving is extremely important [1]
Conventional Friction stir spot welding (FSSW) was invented by Mazda Motor Corporation in 1993 [8], which is similar in concept and appearance to its predecessor Friction stir welding (FSW)
Three distinct regions were revealed in FSSW weld joint: the stir zone (SZ), the thermomechanically affected zone (TMAZ), and heat affected zone (HAZ) [11, 18], and the gray area represented the SZ (Figure 6)

Summary

Introduction

Lightweight metals such as aluminium alloys are increasingly used, especially in aerospace and automotive industries, where weight saving is extremely important [1]. Resistance spot welding, laser spot welding, and riveting have been widely used for aluminium alloys sheet assemblies. Friction stir welding (FSW) was developed by TWI in 1991 [3, 4]. It offers various advantages such as small thermal deformation, sound mechanical properties, fine and uniform weld microstructure, high welding efficiency, and green welding process, which has received considerable attention in welding aluminium alloys [5,6,7]. It shows great potential to be a replacement of single-point joining processes like resistance spot welding and riveting, and it has wider applications in aerospace, aviation, and automobile fields [7].

The Processes of FSSW

Macrostructure and Microstructure of FSSW Joints

Property of FSSW Joints

Modelling of the FSSW Process

Findings

Summary and Perspectives