【摘要】 分析了成分为(%):0.14~0.17C,0.45~0.55Si,1.25~1.45Mn,0.08~0.10V,0.03~0.05Nb H型钢BS55C表面裂纹形成原因。结果表明,该钢凝固时纵裂的敏感性较大,700~950℃范围内的塑性较低,使H型钢表面易产生裂纹。由168炉Nb-V微合金化H型钢BS55C生产数据分析得出,采用LF精炼,控制钢中S≤0.015%、P≤0.020%,优化浇铸水口,采用弱二次水冷工艺,避免在700~900℃范围矫直,可有效减少Nb-V微合金化H型钢的表面裂纹。更多还原

【Abstract】 The causes of surface cracks formation of H beam of Nb-V microalloying steel BS55C-0.14～0.17C,0.45～0.55Si, 1.25～1.45Mn,0.08～0.10V,0.03～0.05Nb have been analyzed.The results showed that the steel was sensitive to longitudinal crack at solidification and its plasticity at 700～950 ℃ was lower,therefore,the cracks were easily produced at surface of H beam.Based on analysis of 168 heats production data of Nb-V microalloying steel BS55C,it was obtained that it was available to effectively decrease the surface cracks of H beam of Nb-V microalloying steel by using LF refining,controlling [S]≤0.015% and [P]≤0.020%,optimizing cast nozzle,adopting weak secondary water cooling and avoiding straightening at 700～900 ℃.更多还原