Development and mechanical evaluation of induction low Shear Friction Stir Spot rivets (ILSFSR) as crack arrest features in co-consolidated and welded thermoplastic laminates

• Published in: Composite structures Vol. 337; p. 118060
• Main Authors: Labordus, Maarten, Sioutis, Ioannis, Tsiangou, Eirini, Schutte, Rutger, Boom, Remie, Tserpes, Konstantinos
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2024
• Subjects: Damage tolerance; Induction Low Shear Friction Stir Riveting; Joints/joining; Mechanical testing; Polymer-matrix composites (PMCs); Damage tolerance; Joints/joining; Mechanical testing; Polymer-matrix composites (PMCs); Induction Low Shear Friction Stir Riveting
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2024.118060

The technique of Induction Low Shear Friction Stir Riveting (ILSFSR) stands as an alternative riveting process, which utilizes the melting and the resolidifying nature of thermoplastic resins to install metallic rivets into thermoplastic laminates without the need for pre-drilling. In this work, the aspects of the method’s implementation are presented, including its theoretical basis, the technical background, the apparatus, and the rivets’ installation procedure. Moreover, a mechanical evaluation of the resulting joints was held to determine their crack-arresting efficiency along carbon fiber reinforced co-consolidated low-melt PolyArylEtherKetone (LM-PAEK) laminates. A coupon scale testing campaign was employed, including mixed-mode Crack Lap Shear specimens containing the ILSFSR features, which were quasi-statically and fatigue-loaded. The interfacial crack growth results, which were compared to reference specimens, indicated the method's potential to provide significant damage retardation, resulting in an increase of 26% of quasi-static interfacial strength and complete confinement of fatigue crack growth, thus aiding in the damage tolerance design for critical engineering components.