Contamination Effect on Composite-to-Metal Adhesive Bond Performance
High performance composite-to-metal joints require reliable manufacturing process to produce repeatable adhesive bond quality. Contamination on pre-bond surfaces stands as a major threat to adhesive bonded structural components. Growing capability in detecting and removing contaminants on pre-bond surfaces has been a strong driving force over years in adhesive bonding applications. In this study, contaminants from multiple sources, including mold release, lubricant and shop environment, were introduced to the pre-bond surfaces. Plasma and laser surface treatments were applied and their effectiveness in removing contaminants was investigated. Surface tension measurement by water contact angle and elemental analysis of surface functionalities by X-ray photoelectron spectroscopy were performed to reveal fundamental surface characteristics and modifications induced by plasma and laser surface treatments. A hybrid composite-to-metal sample configuration was developed for double cantilever beam test. Fracture toughness and associated failure modes were assessed before and after surface treatments. Both plasma and laser surface treatments demonstrated great potentials in enhancing bond performance and removing contaminants.
Author: Xiaomei Fang
Conference: SAMPE Seattle 2017