脉冲涡流, 表面缺陷, 连铸坯, 无损检测

In order to realize surface and near-surface defect on-line monitoring and sorting for high temperature continuous casting billet,a PEC methods was proposed and experimental studies were carried out.Through differential signal analysis and time-domain analysis for the detection coil output signals of eddy current sensor,the feature parameters,such as voltage peak,peak time and zero-crossing time,were extracted,and the impact law of the parameters was studied for point defects,lines defects and star cracks.The research shows that the PEC technology for surface defect monitoring of high temperature continuous casting billet is feasible,and the feature parameters,such as voltage peak,peak time and zero-crossing time,are related closely to defect kind and form,and is laid the foundation for further study on surface defect detection on-line for high temperature continuous casting billet.