Yang Yang,Yuan Qing,Li Zhongbo,et al.Analysis of Fluctuations in Transverse Low-temperature Impact Energy of Q490DRL2 Steel for Pressure Vessels[J].Special Steel,
Yang Yang,Yuan Qing,Li Zhongbo,et al.Analysis of Fluctuations in Transverse Low-temperature Impact Energy of Q490DRL2 Steel for Pressure Vessels[J].Special Steel,DOI:.
Analysis of Fluctuations in Transverse Low-temperature Impact Energy of Q490DRL2 Steel for Pressure Vessels
The Q490DRL2 steel used for large-thickness pressure vessels often exhibits fluctuations in transverse impact energy specifically manifested as significant variations in individual impact values. In this study, for Q490DRL2 steel with a thickness of 48 mm, specimens taken from the half-thickness position with superior and inferior impact energy were comparatively analyzed in terms of microstructural characteristics and inclusion distribution patterns. The results indicate that the matrix microstructures of the two types of specimens are essentially consistent. However, the fracture surface of the specimen with inferior impact energy exhibits a distinct serrated morphology, with numerous fine cracks present near the fracture surface. Some of these cracks pre-existed in the material, while others initiated and propagated during impact loading. Additionally, pronounced microstructural segregation and propagated large-sized cracks were observed in the matrix of this specimen, with fragmented square silicate inclusions visible inside the cracks. In contrast, the fracture surface of the specimen with superior impact energy is relatively flat and smooth, with few observable microcracks and a reduced presence of large inclusion particles in the matrix. In summary, large-particle silicate inclusions and microstructural segregation are the primary factors contributing to the fluctuation in low-temperature impact energy of Q490DRL2 steel used for large-thickness pressure vessels.
Yuan Q , Ren J , Mo J X , et al . Effects of rapid heating on the phase transformation and grain refinement of a low-carbon mciroalloyed steel [J]. Journal of Materials Research and Technology , 2023 , 23 : 3756 - 3771 .
Yuan Q , Xiong L , Liang W , et al . Experimental study on single value fluctuation of impact work in 700 MPa low-alloy tempering plate [J]. Journal of Materials Research and Technology , 2024 , 32 : 565 - 576 .