Detection and evaluation of embedded mild steel can material into 18 Cr-oxide dispersion strengthened steel tubes by magnetic Barkhausen emission

• Published in: Journal of magnetism and magnetic materials 2017-12, Vol.444, p.319-325
• Main Authors: Kishore, G.V.K., Kumar, Anish, Rajkumar, K.V., Purnachandra Rao, B., Pramanik, Debabrata, Kapoor, Komal, Jha, Sanjay Kumar
• Format: Article
• Language: English
• Subjects: Barkhausen effect; Chemical elements; Dispersion; Dispersion hardening steels; Emission analysis; High frequencies; High frequency MBE; Low carbon steels; Low frequency MBE; Magnetic Barkhausen emission (MBE); Magnetic fields; Mild steel; Oxide dispersion strengthened (ODS) steel; Steel; Steel tubes; Studies; Sweep frequency; Thickness
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2017.08.036

•Detection and evaluation of embedded mild steel (MS) into ODS steel tubes by MBE is demonstrated.•High frequency MBE is sensitive for detection of MS on the surface of the ODS steel tube.•Low frequency MBE exhibited MBE RMS voltage peaks corresponding to the MS and the ODS steel.•The ratio of the two peaks can be used for measurement of the thickness of the MS layer.•The sensing depth of LFMBE is found to be more than 1mm. The paper presents a new methodology for detection and evaluation of mild steel (MS) can material embedded into oxide dispersion strengthened (ODS) steel tubes by magnetic Barkhausen emission (MBE) technique. The high frequency MBE measurements (125Hz sweep frequency and 70–200kHz analyzing frequency) are found to be very sensitive for detection of presence of MS on the surface of the ODS steel tube. However, due to a shallow depth of information from the high frequency MBE measurements, it cannot be used for evaluation of the thickness of the embedded MS. The low frequency MBE measurements (0.5Hz sweep frequency and 2–20kHz analyzing frequency) indicate presence of two MBE RMS voltage peaks corresponding to the MS and the ODS steel. The ratio of the two peaks changes with the thickness of the MS and hence, can be used for measurement of the thickness of the MS layer.