Microstructural Evolution and Mechanical Properties of Reeled X65 Pipeline Steel during Cyclic Plastic Deformation and Natural Aging

• DOI: 10.1002/srin.202400719
• Publication Date: 2024-11-06T01:15:01Z
• Authors: Qianlin Wu; Jialu Ge; Ping Hu; Zhonghua Zhang; Chunhua Fan; Ning Zhong
• Keywords: Elongation

The reel laying is recognized as a cost‐effective installation process for offshore pipelines. However, the mechanical properties are modified due to plastic deformation during and lowering of reeled pipelines subsequent natural aging in service. Cyclic (CPD) conducted on X65 pipeline steel simulate strain experienced reel‐laying process, then, CPD specimen aged at 250 °C dislocation configurations gradually evolve from lines tangles into walls cells increase level. After aging, tensile strength increases by about 25 MPa, which not significantly affected last introduced load direction At end compressive loading, yield ratio decrease, but uniform elongation significantly. In contrast, increase, decreases slightly. further level 2 3%. Therefore, modify X65, considerably depending