Optimization of Sensitivity and Reliability of Magnetic Barkhausen Technique for Detecting Hardness Differences on Quenched and Tempered AISI 4140 Steels

Date

2015-06-18

Author

Arslan, Ebru
Davut, Kemal
Şimşir, Caner

Metadata

Show full item record

Item Usage Stats

65
views

0
downloads

Magnetic Barkhausen noise (MBN) technique offers fast and non-destructive inspection of parts against grinding burns. Moreover, the applicability of the technique to evaluate residual stresses, microstructure heterogeneity, hardness, and heat treatment faults has been subject of intense research for the past 10 years. However, the influence of measurement parameters on the sensitivity and reliability of this technique has yet to be studied in detail. The present work aims at comparing the MBN response of quenched and tempered steels at different magnetizing frequency and voltages. For that purpose identical specimens from an AISI 4140 steel bar were quenched and the tempered at various temperatures between 200oC and 600oC. The microstructures were characterized by metallographic examinations and hardness measurements. A linear relation is expected between mechanical hardness and MBN activity due to the linear relation between magnetic coercive force and hardness. The reliability of the MBN measurements were, therefore, evaluated using Pearson’s correlation coefficient between MBN signals and the hardness. In addition sensitivity of the MBN technique was evaluated by comparing the MBN response of the hardest and softest samples; namely the as quenched sample and the sample tempered at 600oC. The MBN activity of the samples was quantified by calculating the root-mean-square (RMS) value of the noise signal obtained. Too low magnetizing voltages cause the MBN signal to be indistinguishable from background noise. Increasing the magnetizing voltage, increases the sensitivity of the MBN. However; saturation magnetization is exceeded in the pick-up coil when too high magnetizing voltages are used. Therefore the most sensitive response of MBN is obtained at an intermediate magnetizing voltage. This optimization work showed that the validity, reliability and sensitivity of Barkhausen noise technique strongly depends on the selection of measurement parameters.

URI

https://hdl.handle.net/11511/79343

Conference Name

11th Int Conf on Barkhausen Noise Micromagnetic Testing (ICBM 11)

Collections

Department of Metallurgical and Materials Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Experimental investigation of hinged and spring loaded rolling piston compressors pertaining to a turbo rotary engine OKUR, MELİH; Akmandor, Ibrahim Sinan (Elsevier BV, 2011-05-01) Hinged rolling piston compressor of a new thermodynamic cycle Pars engine promises high performance figures such as single stage high compression levels and higher volume flow discharge with competitively low input power and torque. The pumping characteristic of the present engine compressor unit has been increased by the implementation of a spring less vane configuration. The reciprocating vane which is usually operated by spring compression in air conditioning and refrigeration unit has been replaced by a...
Investigating the effect of deformation and annealing texture on magnetic anisotropy in low-C steel sheets by magnetic Barkhausen noise method Akçaoğlu, Fehmi Ümit; Gür, Cemil Hakan; Department of Metallurgical and Materials Engineering (2013) Deformation and annealing texture in the cold rolled low carbon steels is important for sheet metal forming operations and service performance. The aim of this study is to non-destructively investigate the effect of texture on magnetic anisotropy. Various samples having different textures and residual stress states, due to different % reduction in thickness, annealing and stress relieving treatment, were prepared. Texture maps were obtained by Magnetic Barkhausen noise measurements performed with 100 steps ...
Prediction of workpiece dynamics and its effects on chatter stability in milling Budak, Erhan; Alan, Salih; Özgüven, Hasan Nevzat (2012-01-01) The workpiece dynamics affect stability in machining of flexible parts. However, it is not a straightforward task to include it in the analysis since the workpiece dynamics continuously change due to mass removal and variation of the cutter contact. In this paper, a methodology for prediction of inprocess workpiece dynamics is presented, which is based on a structural dynamic modification using the FE model of the workpiece. The cutter location (CL) file is used to determine the removed elements at each too...
Determination of welding parameter dependent hot cracking susceptibility of 5086-h32 aluminium alloy with the use of mvt method Batıgün, Caner; Ankara, Osman Alpay; Department of Metallurgical and Materials Engineering (2005) Hot cracking is a serious problem that encounters during welding of aluminium-magnesium alloys. In the present study, solidification and liquation type of hot cracks in weld metal and the heat-affected zones of 5086-H32 aluminium alloy were investigated by using Modified Varestraint Test (MVT) with TIG-AC and TIG-DC welding. With determining the size, type and number of cracks, a relation was established between welding line energy and strain on the hot crack formation. This information was used to determin...
DYNAMIC ANALYSIS OF GEARED ROTORS BY FINITE-ELEMENTS KAHRAMAN, A; Özgüven, Hasan Nevzat; HOUSER, DR; ZAKRAJSEK, JJ (1992-09-01) A finite element model of a geared rotor system on flexible bearings has been developed. The model includes the rotary inertia of shaft elements, the axial loading on shafts, flexibility and damping of bearings, material damping of shafts and the stiffness and the damping of gear mesh. The coupling between the torsional and transverse vibrations of gears were considered in the model. A constant mesh stiffness was assumed. The analysis procedure can be used for forced vibration analysis of geared rotors by c...

Citation Formats

E. Arslan, K. Davut, and C. Şimşir, “Optimization of Sensitivity and Reliability of Magnetic Barkhausen Technique for Detecting Hardness Differences on Quenched and Tempered AISI 4140 Steels,” presented at the 11th Int Conf on Barkhausen Noise Micromagnetic Testing (ICBM 11), İzmir, Türkiye, 2015, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/79343.