The aim of this paper is to investigate the fatigue strength of the Invar alloy weld joints. Invar alloy is commonly used in cryogenic applications where a high degree of dimensional stability is required under temperatures. It is widely used in primary and secondary barriers of membrane-type liquified natural gas (LNG) containment system. The fatigue assessment of Invar alloy weld joints is evaluated based on the nominal stress, structural stress approach and effective notch stress approaches. A series of fatigue tests were carried out for two different types of welded joints with raised edge specimens and overlap joint specimens at room and cryogenic temperatures. The evaluation of the results exhibit that the local stress concept using the reference notch radius of r = 0.05 mm can be applied to the fatigue design of Invar alloy weld joints for plates with thicknesses less than 5 mm. The results are also compared with the available published data. Finite Element Analysis (FEA) is carried out to investigate FAT value and slope of the design curve for Invar alloy weld joints. The suggested fatigue design curves based on the effective notch stress concept indicate a lower FAT value compared to steel weld joints by IIW recommendations.
- Ocean, Offshore and Arctic Engineering Division
Fatigue Assessment of Thin Welded Joints From Invar Alloy by Local Stress Concept
- Views Icon Views
- Share Icon Share
- Search Site
Oh, DJ, Lee, JM, & Kim, MH. "Fatigue Assessment of Thin Welded Joints From Invar Alloy by Local Stress Concept." Proceedings of the ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. Volume 5: Materials Technology; Petroleum Technology. San Francisco, California, USA. June 8–13, 2014. V005T03A023. ASME. https://doi.org/10.1115/OMAE2014-23825
Download citation file: