Process Capability Study for Friction Stir Spot Welding (FSSW)

In this section

Back to Core Research Programme 33632-2021-review-of-materials-am-and-nde-considerations-for-functionally-graded-materials 34236-2023-literature-review-on-the-potential-use-of-non-destructive-testing-techniques-for-residual-stress-measurement 34241-2023-artificial-intelligence-for-ndt-scanning-of-unknown-geometries-using-collaborative-robots 34459-2022-friction-stir-welding-of-pressure-vessel-liners-for-the-storage-and-transportation-of-hydrogen 34727-2023-techniques-for-high-temperature-ultrasonic-inspection-of-arc-welding-state-of-the-art-review 34793-2023-update-on-literature-reviews-for-wire-fed-additive-manufacturing 34847-2023-Literature-review-on-crack-length-measurement-techniques-on-environmental-fracture-toughness-tests 35268-2024-Literature-review-on-dual-sensing-applications-for-SHM-of-pipelines 32221-2020-hybrid-composite-to-metal-joining 32893-2020-mechanical-fastener-coatings-for-corrosion-protection 33557-2020-extreme-high-speed-laser-application-ehla-coatings 33557-2020-extreme-high-speed-laser-application-ehla-coatings 33557-2020-extreme-high-speed-laser-application-ehla-coatings 33557-2020-review-of-electric-vehicle-battery-joining-methods-and-testing 34250-2022-thermoplastic-materials-compatibility-for-hydrogen-service A Review of High Power, In-Vacuum and Narrow Gap Laser Welding Processes for Thick Section Welding A Review of High Productivity Additive Manufacture Using a Hybrid Laser-Arc Deposition (HLAD) Process A Review of Micro Welding with Fibre and Disc Continuous-Wave Laser Sources A Review of Residual Stress Measurement Techniques Used for Components Produced Using the Selective Laser Melting Process A Review of the Machine GTAW Ambient Temperature Temper Bead Repair Technique for Nuclear Power Plant Components A Review of Weld Repairs of Mar-M247 and Similar Alloys Applications, Modelling and Manufacturing Processes for Perforated Composites - Literature Review Butt Fusion Welding Procedures and Test Methods Used for PE Pipes Duplex Stainless Steel Welding – A Review of Current Practices Elastic Follow-Up in the Context of Fracture Assessment Flaw Sizing Techniques Using Guided Waves Flaw Sizing Techniques Using Guided Waves Flaw Sizing Techniques Using Guided Waves In-Bore Multi-Positional Laser Welding In-Process Monitoring of Arc Welding for Quality and Defect Detection Mechanical Fastening Technologies for Steel to Aluminium Joining in Automotive Manufacture Process Capability Study for Friction Stir Spot Welding (FSSW) Resistance Spot Welding with Transition Discs – A Review of Dissimilar Joining Using Transition Materials with Specific Reference to Resistance Spot Welding Review of Process Simulations for Metal Additive Manufacturing Surface Modification and Micro-Machining with Pulsed-Laser Sources Wire Fed Electron Beam Additive Manufacture – A State-of-the-Art Review

Process Capability Study for Friction Stir Spot Welding (FSSW) Technical Literature Review 23973

TWI Technical Literature Review 23973

By Khalid Nor and Dwight Burford

Background

This technical review provides an overview of FSSW principles and practices based on a literature and industry survey.

Friction stir spot welding (FSSW) is a solid state welding process in which the baseline enabling technology is friction stir welding (FSW). In conventional FSSW, the non-consumable FSW tool is used without any linear movement thereby producing a localised joint where the tool was plunged into the material. This single-point joint is similar to a resistance spot and rivet joint. Friction stir spot welding is presently being used by transportation industries to form small aspect ratio (SAR) discrete lap joints between sheets of malleable materials, typically in aluminium alloys, magnesium alloys and zinc coated steel. It is also used to join sheets to supporting structures like frames and beams.

With conventional FSSW, the small welded area and exit hole left after the tool is retracted has caused concerns in terms of structural integrity, especially in safety critical applications. Many variants have emerged to address the concerns including: swept, stitch, swing, refill, probeless and other miscellaneous variants. The different FSSW techniques for forming discrete joints are individually described and weld property data presented. Comparisons made are also made between process variants.

In the literature search it was found that on-going research is looking at FSSW for applications in the automotive and aerospace sectors, with a view to replacing the current conventional techniques used. Research work is on-going to identify the requirements to reduce or eliminate the barriers to implement FSSW, especially in the aerospace sector. For aerospace applications, FSSW without an exit hole would be desirable, although swept FSSW has shown its potential against riveted panels. Also in the aerospace sector, accepted and recognized standardized joint design values/data for strength properties of materials are required. In the automotive industry, the main push for FSSW is to minimise the welding time when compared against the RSW and (SPR) processes. Although much work on basic FSSW has been done, the barrier is still is the longer welding time for automotive. The probeless FSSW process is tipped to be a solution for aluminium to steel joints for automotive.