Q345B无缝钢管结疤缺陷原因分析

Analysis on Scare Defects of Q345B Seamless Steel Pipe

通过金相显微镜(OM)、扫描电镜及能谱仪(SEM-EDS)对Q345B钢管外壁的结疤缺陷进行检测分析,结果表明结疤缺陷实际上是典型的外表面折叠缺陷,是由钢坯表面存在微裂纹,经加热炉加热后裂纹周围高温氧化,在后续轧制过程中进一步扩展形成的。

Scare defects of outer wall of Q345B seamless steel pipe were detected by optical microscopy （OM）, scanning electron microscopy and energy dispersive spectroscopy （SEM -EDS）. The result showed scare defects actually typical exterior folding defects, which were caused by the micro - cracks of billet surface that oxidized in high temperature after heating by heating furnace and extend further in later rolling process.