Abstract: To simulate compact strip production (CSP) technology, the effect of Nb-Ti on structure and mechanical properties of 400 MP and 460 MPa high strength weathering steel-0.060～0.076C,0.25～0.31Cu,0.45～0.56Cr 0.29~0.30Ni has been studied by 10 kg vacuum induction furnace melting and rolled into 6 mm plate. The results showed that yield strength o, and tensile strength oi, of steel contained 0.03% Ti were respectively 450 MPa and 545 MPa,o, snd og of steel contained 0.03%Nb-0.02% Ti were 550 MPa and 615 MPa,and c, and on of steel no-contained Nb and Ti were only 375 MPa and 480 MPa.The structure of 400 MPa weathering steels were ferrite + minor pearlite, and the main precipitates of steel contained Ti were CuS₂(20~25 nm)and TiN (80 nm);the structure of 460 MPa steel contained Nb-Ti was mainly granular bainite with precipitates CuS2 and(NbTi)CN(30~60 nm)therefore the strength of steel increased.

摘要： 为模拟CSP(紧凑式带材生产 )工艺 ,由实验室 10kg真空感应炉冶炼后轧成 6mm钢板 ,试验研究了Nb、Ti对成分 (% )为 0 0 6 0～ 0 0 76C ,0 2 5～ 0 31Cu ,0 4 5～ 0 5 6Cr,0 2 9～ 0 30Ni的 4 0 0MPa和 4 6 0MPa级高强度耐候钢组织和性能的影响。结果表明 ,含 0 0 3%Ti钢σs 和σb 分别为 4 5 0MPa和 5 4 5MPa ,含 0 0 3%Nb、0 0 2 %Ti钢σs 和σb 分别为 5 5 0MPa和 6 15MPa ,不含Nb、Ti钢σs 和σb 仅为 375MPa和 4 80MPa。 4 0 0MPa级耐候钢的组织为铁素体 +少量珠光体 ,含Ti钢的主要析出物为CuS2 (2 0～ 2 5nm)和TiN(80nm) ,含Nb、Ti4 6 0MPa级钢的组织主要为粒状贝氏体 ,析出物CuS2 和 (NbTi) CN (30～ 6 0nm) ,从而提高了钢的强度。

关键词: 高强度耐候钢, Nb, Ti , 微合金化