水电工程用800MPa级高强钢的研发与应用  

Development and Application of 800 MPa High Strength Steel for Hydropower Project

作　　者：刘心阳 LIU Xinyang(Plate Business Unit)

机构地区：[1]板材事业部

出　　处：《南钢科技与管理》2022年第3期6-11,共6页NISCO Technology and Management

摘　　要：采用低C、低Ceq、低Pcm及微合金化的成分设计,成功开发了60 mm厚水电工程用800 MPa级高强度钢板,产品质量满足低焊接裂纹敏感性、低焊接预热温度、高强度、低温韧性等苛刻的交货要求,其中抗拉强度≥800 MPa,屈强比≤0.95,断后延伸率≥18%,-40℃横向冲击功≥180 J,Pcm≤0.23,完全满足设计院对于800 MPa级高强度水电用钢的技术要求。金相照片表明,钢板组织为回火贝氏体+回火马氏体组织,原奥氏体晶粒内部呈各向板条束状均匀分布,碳化物均匀分布在板条束上,保证了钢板的强韧性匹配。焊接试验表明,钢板可以满足70℃低预热条件焊接,焊接接头综合力学性能优良。By adopting the composition design of low C,low Ceq,low Pcm and microalloying,a 60 mm thick 800 MPa high strength steel plate for hydropower project has been successfully developed.The product quality meets the strict de-livery requirements of low welding crack susceptibility,low welding preheating temperature,high strength and low tem-perature toughness(tensile strength≥800 MPa,yield ratio≤0.95,elongation after fracture≥18%,transverse impact energy at-40℃≥180J,Pcm≤0.23),which fully meet the technical requirements of 800 MPa high strength steel for hydropower proposed by the designing institute.The metllographie photos show that the structure of the steel plate is tempered bainite+tempered martensite,the original austenite grains are uniformly distributed in the shape of isotropic lath bundles,and the carbides are evenly ditributed on the lath bundles,which ensures the matching of strengh and toughness of the steel plate.The welding test shows that the steel plate can be welded with low preheating temperature of 70℃,and the comprehensive mechanical properties of the welded joints are excellent.

关 键 词：水电用钢 800 MPa高强钢 低焊接裂纹敏感性 可焊性 

分 类 号：TG1[金属学及工艺—金属学]