Improving Fatigue Performance of Laser-Welded 2024-T3 Aluminum Alloy Using Dry Laser Peening
Open Access
- 6 November 2019
- Vol. 9 (11), 1192
- https://doi.org/10.3390/met9111192
Abstract
The purpose of the present study was to verify the effectiveness of dry laser peening (DryLP), which is the peening technique without a sacrificial overlay under atmospheric conditions using femtosecond laser pulses on the mechanical properties such as hardness, residual stress, and fatigue performance of laser-welded 2024 aluminum alloy containing welding defects such as undercuts and blowholes. After DryLP treatment of the laser-welded 2024 aluminum alloy, the softened weld metal recovered to the original hardness of base metal, while residual tensile stress in the weld metal and heat-affected zone changed to compressive stresses. As a result, DryLP treatment improved the fatigue performances of welded specimens with and without the weld reinforcement almost equally. The fatigue life almost doubled at a stress amplitude of 180 MPa and increased by a factor of more than 50 at 120 MPa. DryLP was found to be more effective for improving the fatigue performance of laser-welded aluminum specimens with welding defects at lower stress amplitudes, as stress concentration at the defects did not significantly influence the fatigue performance.Keywords
Funding Information
- Ministry of Education, Culture, Sports, Science and Technology (Q-LEAP-JPMXS0118068348)
- Japan Society for the Promotion of Science (JP16H04247, JP16K14417, 19K22061)
This publication has 42 references indexed in Scilit:
- Laser Shock Peening, the Path to ProductionMetals, 2019
- Femtosecond Laser Peening of Friction Stir Welded 7075-T73 Aluminum AlloysJournal of the American Academy of Dermatology, 2018
- Femtosecond laser peening of 2024 aluminum alloy without a sacrificial overlay under atmospheric conditionsJournal of Laser Applications, 2016
- Shock tacticsNature Photonics, 2009
- Retardation of crack initiation and growth in austenitic stainless steels by laser peening without protective coatingMaterials Science and Engineering: A, 2006
- Laser shock processing and its effects on microstructure and properties of metal alloys: a reviewInternational Journal of Fatigue, 2002
- Physics and applications of laser-shock processingJournal of Laser Applications, 1998
- Residual stress improvement in metal surface by underwater laser irradiationNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1997
- Laser shock-induced microstructural and mechanical property changes in 7075 aluminumJournal of Applied Physics, 1972
- LASER-GENERATED STRESS WAVESApplied Physics Letters, 1970