Evaluation of Solvay's FusePly (trademark) for Prebond Composite Surface Preparation (CRADA 17-307-RX-01 Task 2 Project 1)
Abstract:
The use of adhesive bonding in lieu of fasteners to join composite components enables advantages in manufacturing and design. Elimination of fasteners can lead to reduced manufacturing cost, optimized structures, and fewer parts. Adhesive joining benefits are realized due to reduced stress concentrations around holes and distribution of structural loads across a larger area as compared to traditional fastening methods. Additionally, adhesive joining can potentially reduce manufacturing flow time. However, the certification of bonded structures is challenging, in large part due to risks associated with defined interfaces in cobonded and secondarily bonded joints. Surface preparation is critical; if not sufficient, adhesion failure at one of these interfaces can cause structural failure at lower than expected loads. Documents such as the Federal Aviation Administration (FAA) Advisory Circular No. 20-107B, "Composite Aircraft Structure 1," and the United States Department of Defense (DoD) Joint Service Specification Guide (JSSG)-2006, "Aircraft Structures 2 ," state a qualified adhesive bonding process must be repeatable and reliable, leading to thorough and costly testing.