影响S460M钢板韧性的因素分析

Analysis on Factors Influencing the Toughness of S460M Steel Plate

根据韶钢生产S460M钢板的冲击功分布情况,分析了典型冲击功不合格试样的断口形貌及微观组织。结果表明:由于成分设计及生产工艺制定不合理,导致钢板中心偏析严重,厚度方向晶粒差异较大,越往中心晶粒越粗大。晶粒粗大且分布不均匀致使晶间结合力减弱,裂纹扩展阻力变小,最终导致钢板韧性变差。

According to the impact energy distribution of S460M steel plate produced by Shaogang, analysis is performed on the fracture morphology and microstructure of typical specimen with disqualified impact energy. The re-sults show that the improper composition design and production process plan lead to severe central segregation, large difference of grain size in thickness direction, coarser grain at plate center. The nonuniform distribution of coarser grain weakens the intercrystalline bonding force, reduces the crack propagation resistant force and deteriorates the toughness of steel plate.