Laser Surface Preparation for Adhesive Bonding II. Task Order 5TS5703D035S

摘要

For several years, research has been undertaken for the U.S. Air Force to assess the utility of pulsed laser beams in the cleaning of surfaces without the use of solvents or abrasives. Initial efforts led to the development of a prototype laser-based cleaning system that could effectively remove paint, contaminants, and oxides from metal surfaces such as aluminum, stainless steel, and titanium. In follow-on research, the basic laser cleaning concepts were applied to the development of a more powerful and user-friendly Advanced Laser Cleaner Prototype. This advanced prototype was then employed in a program to investigate the feasibility of using pulsed laser cleaning as part of a prebond treatment process for aluminum surfaces. The results of the latter program clearly showed that compact laser systems employing flexible fiber optic beam transport to a handheld beam delivery tool can successfully pretreat aluminum surfaces prior to their preparation for adhesive bonding by means of a sol-gel process. In bond durability tests, the laser-pretreated surfaces generally performed as well as standard solvent wipe/grit blast pretreatment techniques.