The Department of Defense (DoD), National Aeronautics and Space Administration (NASA), and industry coat weapons systems, airframes, components, and associated equipment primarily for corrosion protection. Current methods for small area and supplemental removal of coatings are costly, time consuming, labor-intensive, and result in undesirable environmental conditions. This ESTCP and Joint Group on Pollution Prevention project validated an innovative coating removal system using handheld portable laser technology.
Low-power, lightweight, handheld portable lasers were demonstrated to validate their use as an effective and environmentally safe alternative to existing depainting processes. These systems were used to remove traditional paint systems from small areas, irregular surfaces, various components, support equipment, and hard-to-reach areas on aircraft. The handheld laser systems were required to remove the current coating systems from aerospace materials, including aluminum, steel, and composites, without causing unacceptable damage to the substrate. During the demonstration, the following three laser types were investigated: carbon dioxide (CO2), neodymium: yttrium-aluminum-garnet (Nd:YAG), and diode. These systems were selected based on their performance during screening tests and on the availability of a commercial-off-the-shelf (COTS) cleaning/coating removal system. Results were compared to the requirements identified by DoD, NASA, and industry partners in a Joint Test Protocol.
This project showed that the portable handheld Nd:YAG laser systems do not significantly affect the substrate materials and are considered an effective, versatile tool that can be used for coating removal applications. As a result of this demonstration, hand held laser systems have been procured and are in the process of implementation at each of the Air Force Air Logistics Centers. Additionally, the Army has procured similar systems and is in the process of implementing the technology at Fort Rucker.
The DoD, NASA, and industry remove coatings from weapons systems, component parts, and other equipment for a variety of reasons. Safe and efficient coating removal processes save both time and money. A cost benefit analysis performed for this project showed an annual cost savings of $100 thousand and a life cycle cost savings of $1.2 million at one Air Logistics Center from eliminating/minimizing chemical stripping purchases and associated waste streams. The cost benefit analysis was performed based on the use of lasers for a single coating removal step. Once laser technology is applied to a broader range of processing steps, the cost benefits will increase dramatically. In addition to cost savings, implementing the laser coating removal technology will assist depots in meeting the National Emission Standards for Hazardous Air Pollutants and Clean Air Act requirements. (Project Completed - 2005)