High-Power Laser System for Repairing Al-Mg Alloy Ship Plates
Abstract
The use of 5000 series Al-Mg alloys is increasing across theU.S. Navy due to their combination of tunable strength/ductility, weldability, and corrosionresistance. These alloys offer the ability to decrease the structural weight of a ship, thusincreasing the speed, range, and fuel economy of the ship. For these alloys, the intergranularcorrosion and intergranular stress corrosion cracking (IG/IGSCC) caused by sensitization andtensile stress are the main factors that lead to the eventual failure of the alloy. To meet the U.S.Navy~s goal of reducing operation, maintenance, and support costs associated with 5000 seriesAl alloy sensitizations, the PI~s group proposed to develop a compact, portable, energy-saving,chemical-free, maintenance-free, and easy to operate laser repair system to remove pits andcracks in sensitized Al alloy surfaces and condition the surfaces to improve the resistance tofurther sensitization. Significant technical progress is required in the following areas: removal ofthe surface contamination existing in the sensitized regions using laser cleaning; use of laserheating to diffuse ~ phase precipitation residual back to the Al alloys (desensitization);introduction of compressional stress on alloy surface to prevent intergranular stress corrosioncracking; and development of a compact portable laser repair system.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 05, 2017
- Source ID
- N000141712489
Entities
People
- Yongfeng Lu
Organizations
- Office of Naval Research
- United States Navy