铌微合金化异形坯翼缘横裂纹成因分析

Study on the Formation of Transverse Cracks in the Flange of Nb Microalloyed Beam Blank

针对铌微合金化异形坯表面横裂纹在翼缘顶端和翼缘内侧发生率较高的问题,通过对异形坯的夹杂物、高温热塑性、表面温度分布、等效应力进行系统研究,揭示了异形坯铌微合金化钢在翼缘顶端和翼缘内侧的横裂纹的产生原因。通过优化工艺和提高设备精度,有效地控制了异形坯横裂纹的产生,异形坯轧后裂纹修磨率下降了13%。

In view of the high occurrence rate of transverse cracks on the surface of the beam blank of Nb microalloyed steel at the top and inner sides of the flange.Through systematic research on inclusions,high-temperature plasticity,surface temperature,and equivalent stress behavior of beam blank,The generation mechanism of transverse cracks in Nb microalloyed steel at the top and inner sides of the flange was revealed.With improvement in process and equipment,the crack is effectively controlled,and the crack repair rate of the beam blank after rolling was reduced by 13%.