June 19, 2022
Journal Article

Significant slowdown of plasma-optimized surface energy deactivation by vacuum sealing for efficient adhesive bonding

Abstract

This work proposes an approach to minimize surface energy deactivation of plasma-treated metal and carbon fiber-reinforced polymer (CFRP) surfaces by vacuum sealing. Plasma treatments enhance adhesive wettability on post-treated surfaces for adhesive joints, but the treated surfaces deactivate quickly in air. The surface energy of aluminum alloy AA6061 and carbon fiber-reinforced polymer-polyamide (CFRP-PA66) optimally treated by a blown air plasma instrument returns to the original surface energy within one hour. Vacuum sealing of AA6061 and CFRP-PA66 reduced the surface energy deactivation over 7 days by at least 230 times and 970 times compared to in air. Double Cantilever Beam (DCB) tests performed on adhesively-bonded AA6061/CFRP-PA66 joints showed that the total energy release and energy dissipation before failure of plasma-treated and vacuum-sealed materials was up to 60% more than plasma-treated materials without vacuum sealing and up to 125% more than non-plasma-treated materials.

Published: June 19, 2022

Citation

Shin Y., Y. Qiao, N.L. Canfield, Z. Yu, H. Meyer, D.R. Merkel, and E.K. Nickerson, et al. 2022. Significant slowdown of plasma-optimized surface energy deactivation by vacuum sealing for efficient adhesive bonding. Composites Part B: Engineering 240. PNNL-SA-170346. doi:10.1016/j.compositesb.2022.110001