基于脉冲涡流技术的连铸坯表面缺陷检测.pdf

基于脉冲涡流技术的连铸坯表面缺陷检测欧阳奇张敏赵立明等———暋暋暋基于脉冲涡流技术的连铸坯表面缺陷检测欧阳奇张敏赵立明张立志暋重庆大暋学暋重庆暋400044摘要为了实现高温连铸坯表面及近表面缺陷在线检测和缺陷坯及时分拣提出了连铸坯表面缺陷:脉冲涡流检测方法并进行了实验研究。对连铸坯表面缺陷的脉冲涡流检测信号进行差分分析和时域分析提取了连铸坯表面缺陷信号的电压峰值、峰值时间及过零时间等特征量并分析得到点缺陷、线缺陷、星状裂纹等缺陷对脉冲涡流检测信号特征值的影响规律。研究表明采用脉冲涡流技术实现高温连铸坯表面及近表面缺陷的无损在线检测技术是可行的电压峰值、过零时间和峰值时间与缺陷种类及缺陷的形态密切相关为进一步研究高温铸坯表面缺陷检测和重构奠定了基础。关键词脉冲涡流表面缺陷连铸坯无损检测:;;;中图分类号文章编号:TF777暋暋暋:1004—132X(2010)10—1235—05StudyonContinuousCastingBilletSurfaceDefectDetectionBasedonPulsedEddyCurrentTechniqueOuyangQi暋ZhangMin暋ZhaoLiming暋ZhangLizhiChoninUniversitChonin400044Abstractgqgygqg:Inordertorealizesurfaceandnear-surfacedefecton-linemonitoringandsortingforhightemperaturecontinuouscastingbilletaPECmethodswasproposedandexperimentalstudieswerecarriedout.Throughdifferentialsignalanalysisandtime-domainanalysisforthedetectioncoiloutputsignalsofeddycurrentsensorthefeatureparameterssuchasvoltagepeakpeaktimeandzero-crossingtimewereextractedandtheimpactlawoftheparameterswasstudiedforpointdefectslinesdefectsandstarcracks.TheresearchshowsthatthePECtechnologyforsurfacedefectmonitoringofhightemperaturecontinuouscastingbilletisfeasibleandthefeatureparameterssuchasvoltagepeakpeaktimeandzero-crossingtimearerelatedcloselytodefectkindandformandislaidthefoundationforfurtherstudyonsurfacedefectdetectionon-lineforhightemperaturecontinuouscastingbillet.Keywords:pulsededdycurrent(PEC);surfacedefect;continuouscastingbillet;NDT引言