Composite-to-composite Bonding using Scotch-WeldTM AF-555M Structural Adhesive:

Processing and properties of composite-to-composite bonding using Scotch-Weld TM AF-555M structural adhesive were investigated. Bonding surfaces of T800H/3900-2 composite were prepared by co-curing the dry and wet peel-plies. Surface topologies of the peel-plies and the co-cured composite surfaces were examined by microscopy, contour mapping using a coordinate measuring machine equipped with a ruby sphere probe, and contact angle goniometry. Curing of the adhesive was conducted in an autoclave or vacuum press at 177°C (350°F) for 2 h under 310 KPa (45 psi). Common bagging practices for composite fabrication in an autoclave were followed. It was found that a prolonged vacuum application (i.e., overnight) prior to the application of temperature and pressure was a critical element to produce porosity-free, high-quality bonds with this adhesive system. Following this procedure, a strong bond line was consistently produced, which routinely provided a single-lap shear strength more than 10% higher than the nomi...