Evaluation of fatigue strength based on dissipated energy for laser welds

• Published in: Infrared physics & technology Vol. 125; p. 104288
• Main Authors: Ogawa, Yuki, Horita, Taiju, Iwatani, Naoki, Kadoi, Kota, Shiozawa, Daiki, Sakagami, Takahide
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2022
• Subjects: Fatigue limit estimation; Fracture origin; Laser welding; Lasers; Fatigue limit estimation; Fracture origin; Lasers; Laser welding
• ISSN: 1350-4495; 1879-0275
• DOI: 10.1016/j.infrared.2022.104288

•Fatigue limit estimation for laser welds based on temperature change was discussed.•Temperature changes due to microplastic deformation were measured.•Fatigue tests on multiple specimens revealed the fatigue strength of laser welds.•Fatigue limit was almost consistent with stress amplitude at which temperature rose.•The area with the highest temperature increase was the fracture origin. To ensure the safety and reliability of welded structures, its fatigue characteristics need to be identified. This study proposed the fatigue limit estimation of steel laser welds based on a temperature change due to dissipated energy to establish a rapid evaluation method for the fatigue strength of steel laser welds. The area at which the temperature increase due to dissipated energy was locally high was the fracture origin for steel laser welds. The stress amplitude at which the specimen displayed the temperature increase due to dissipated energy approximately coincided with the fatigue limit for steel laser welds. Therefore, the temperature change due to dissipated energy was used to identify the fracture origin of steel laser welds and was almost evaluated the fatigue limit in a short period of time.