Fatigue Performance of Metal–Composite Friction Spot Joints

• Published in: Materials Vol. 14; no. 16; p. 4516
• Main Authors: Goushegir, Seyed Mohammad, Santos, Jorge F. dos, Amancio-Filho, Sergio T.
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 11-08-2021; MDPI
• Subjects: Adhesive bonding; Aircraft; Alloys; Aluminum alloys; aluminum and alloys; Aluminum base alloys; Carbon fibers; Composite materials; Dynamic loads; Fatigue life; Feasibility studies; Fiber reinforced materials; Friction; friction spot joining; Interfacial bonding; Investigations; Joining; mechanical properties; Metal fatigue; Polymer matrix composites; Polymers; Polyphenylene sulfides; Shear strength; surface preparation; Surface treatment; Germany
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14164516

Friction spot joining is an alternative technique for joining metals with polymers and composites. This study investigated the fatigue performance of aluminum alloy 2024/carbon-fiber-reinforced poly(phenylene sulfide) joints that were produced with friction spot joining. The surface of the aluminum was pre-treated using various surface treatment methods. The joined specimens were tested under dynamic loading using a load ratio of R = 0.1 and a frequency of 5 Hz. The tests were performed at different percentages of the lap shear strength of the joint. Three models—exponential, power law, and wear-out—were used to statistically analyze the fatigue life of the joints and to draw the stress–life (S–N) curves. The joints showed an infinite life of 25–35% of their quasi-static strength at 106 cycles. The joints surpassing 106 cycles were subsequently tested under quasi-static loading, showing no considerable reduction compared to their initial lap shear strength.