Quality Control of Adhesive Bonding

The quality control of adhesive bonded panels begins with the arrival of the adhesive system at the fabricating facility. Whether an adhesive must be kept refrigerated or stored at room temperature, its quality must be verified and maintained until it is cured in a bonded assembly. Panel detail prefit, surface preparation, curing temperature, and pressure must all be maintained within prescribed parameters to obtain part quality. The utilization of process verification coupons adds assurance of correct processing and verifies the strength of the bond assembly. Nondestructive Inspection (NDI) is a valuable tool used to provide final assurance of correct processing. NDI comes in many shapes, and selection of the method to be employed must be given careful consideration. Underinspection can make the assemblies cost prohibitive. A few of the methods available will be discussed from visual inspection to ultrasonic through transmission with “C” scan recordings.