Title: Influence of Various Surface Preparation Techniques on Resistance Welded and Adhesively Bonded Unidirectional Thermoplastic Composite Joints

Authors: Waruna P. Seneviratne, John S. Tomblin, Brandon L. Saathoff

DOI: 10.33599/nasampe/s.21.0487

Abstract: Reinforced thermoplastic composites are an attractive material solution for many commercial and defense aerospace applications due to their ability to reduce weight, manufacturing cycle time, and cost. In addition, thermoplastic composites have superior toughness and environmental resistance compared to thermoset composites and offer the ability to be joined by welding over traditional methods such as mechanical fastening or adhesive bonding. Compared to an adhesive bonded joint, thermoplastic welded joints do not require extensive surface preparation techniques to be applied since the thermoplastic polymer material is melted at the interface and joined. Although this is the case, the effect of various surface preparation methods on resistance welded joints was investigated to highlight potential changes in joint performance. Findings were compared to surface preparation effects on adhesively bonded joint performance. Several surface preparation techniques were considered, including hand sanding, grit blasting, and atmospheric plasma treatments. The surface morphology and surface free energies were characterized for each surface preparation method, and the corresponding single lap-shear strength results were compared.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000487

Pages: 12

Price: FREE