Nondestructive evaluation of steels using acoustic and magnetic barkhausen signals—I. Effect of carbide precipitation and hardness
TL;DR: In this article, the effect of microstructures on acoustic and magnetic Barkhausen signals has been investigated in a quenched and tempered steel and spheroidized steels with various carbon contents.
About: This article is published in Acta Metallurgica.The article was published on 1987-07-01. It has received 114 citations till now. The article focuses on the topics: Barkhausen effect & Barkhausen stability criterion.
Citations
More filters
TL;DR: A review of the current understanding of the subject, giving were possible examples of the approach and techniques used to obtain this, can be found in this paper, where the authors also highlight areas of current research activity and indicate the type of work still required to provide information on aspects that currently lack a full understanding.
213 citations
TL;DR: In this paper, the influence of applied tensile stress and grain size on Magnetic Barkhausen Noise and hysteresis loops in 1005 commercial steel is studied, and the results show that MBN can be utilized to evaluate changes in the microstructural and mechanical properties of commercial carbon steels.
127 citations
30 Aug 1999-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the characteristics of the Barkhausen noise phenomenon for various crystalline microstructures of plain steels are investigated using the same magnetisation rate for different materials, specially developed to provide fully reproducible experimental conditions.
Abstract: The characteristics of the Barkhausen noise phenomenon are investigated for various crystalline microstructures of plain steels. The measurements of the magnetic Barkhausen noise (MBN) and of the acoustic Barkhausen noise (ABN) are performed using the same magnetisation rate for different materials, specially developed to provide fully reproducible experimental conditions. The MBN fingerprints of single constituent steels (ferrite, pearlite and martensite) are first studied. Then, examples of MBN characteristics for more complex microstructures are presented. The results concerning single constituent steels are discussed in terms of shape, amplitude and position of the MBN and ABN fingerprints, taking into account two main aspects: the elementary Barkhausen events (sources), linked to the interaction of the magnetic domain microstructure with the crystalline microstructure, and the propagation of the electromagnetic waves in the material as well as its detection at the pick-up coil, both strongly influencing the frequency spectrum of the detected signal. This approach enables us to get a better understanding of the dependency of Barkhausen noise on the crystalline microstructure, which is then used to explain the characteristics of MBN observed for more complex microstructures.
101 citations
TL;DR: In this article, the effect of tempering on the magnetic Barkhausen noise (MBN) signal profile was studied in case-carburised EN36 steel using a range of magnetic excitation frequencies and a number of frequency ranges for analysis of the MBN signal.
Abstract: The effect of tempering on the magnetic Barkhausen noise (MBN) signal profile was studied in case-carburised EN36 steel using a range of magnetic excitation frequencies and a number of frequency ranges for analysis of the MBN signal The MBN level generally increases with tempering due to coarsening of the microstructure With higher values of excitation frequency, f EX , the MBN profile exhibits a single peak, but with low values of f EX , double peaks are observed The MBN peak obtained with higher f EX was found to correlate well with hardness changes in a region, down to 100 μm below the surface The analysis of the MBN signal produced with low f EX , in narrow frequency ranges selected by software frequency filtering, showed variations in the extent of changes in the relative height of the two MBN peaks in the profile After taking into account the skin depth-frequency relation for the MBN signal, variations in the values of the two MBN peaks in different analysing frequency ranges were found to correlate well with hardness variations at different depths down to 425 μm below the surface An empirical relationship has been established between the hardness-depth profile and the MBN measurements
86 citations
TL;DR: In this paper, the authors discuss the progress made in the application of non-destructive testing (NDT) techniques in evaluating various microstructural features and mechanical properties with emphasis on recent studies.
Abstract: Non-destructive evaluation (NDE) of materials for characterising various key microstructural features, mechanical properties (tension, creep, fatigue crack growth, hardness and fracture toughness), deformation and damage mechanisms has attracted considerable attention in the past 20 years as a primary step towards ensuring structural integrity of components. However, until recently, the correlations between the various NDE parameters and material properties have been only empirical and based on physical principles. The interaction between the NDE probing medium and the mechanical behaviour is not yet fully understood. The purpose of this review is to discuss the progress made in the application of non-destructive testing (NDT) techniques in evaluating various microstructural features and mechanical properties with emphasis on recent studies. Reinterpretation of older data, in the light of present understanding of the interaction of the NDE probing medium with material parameters, is carried out selectively. The NDT techniques evaluated include acoustic emission, ultrasonic attenuation and velocity, magnetic hysteresis parameters, magnetic Barkhausen emission, acoustic Barkhausen emission, laser interferometry, positron annihilation, X-ray diffraction and small angle neutron scattering. Critical assessments of the applicability of the various NDE techniques for the material parameters are provided.
78 citations
References
More filters
Book•
[...]
01 Jan 1964
TL;DR: Paleomagnetism is the study of the magnetic properties of rocks as discussed by the authors, and it is one of the most broadly applicable disciplines in geophysics, having uses in diverse fields such as geomagnetic, tectonics, paleoceanography, volcanology, paleontology, and sedimentology.
Abstract: Paleomagnetism is the study of the magnetic properties of rocks. It is one of the most broadly applicable disciplines in geophysics, having uses in diverse fields such as geomagnetism, tectonics, paleoceanography, volcanology, paleontology, and sedimentology. Although the potential applications are varied, the fundamental techniques are remarkably uniform. Thus, a grounding in the basic tools of paleomagnetic data analysis can open doors to many of these applications. One of the underpinnings of paleomagnetic endeavors is the relationship between the magnetic properties of rocks and the Earth’s magnetic field. In this chapter, we will review the basic physical principles behind magnetism: what are magnetic fields, how are they produced, and how are they measured? Although many find a discussion of scientific units boring, much confusion arose when paleomagnetists switched from “cgs” to the Système International (SI) units, and mistakes abound in the literature. Therefore, we will explain both unit systems and look at how to convert successfully between them. There is a review of essential mathematical tricks in Appendix A, to which the reader is referred for help.
2,365 citations
TL;DR: Granular inclusions, grain boundaries, lamellar precipitates, and the crystalline surface have been examined as possible nucleation centers for domains of reverse magnetization in ferromagnetic materials as discussed by the authors.
Abstract: Granular inclusions, grain boundaries, lamellar precipitates, and the crystalline surface have been examined as possible nucleation centers for domains of reverse magnetization in ferromagnetic materials. It is concluded that the surface density of magnetic poles at the grain boundaries ${\ensuremath{\omega}}^{*}$ is the most common source of nucleation energy in polycrystalline materials.
243 citations
187 citations
TL;DR: In this paper, the influence of intergranular impurity segregation on acoustic and magnetic Barkhausen signals induced during magnetization in an undoped nickel-chromium steel and doped steels with antimony, tin or phosphorus was studied.
51 citations
TL;DR: In this paper, the effect of stress on the magnitude of acoustic emission during magnetization of mild steel and nickel has been investigated, and it has been shown that the acoustic emission shows a strong dependence on stress.
Abstract: The effect of stress on the magnitude of acoustic emission during magnetization of mild steel and nickel has been investigated. It has become clear that the magnitude of acoustic emission during magnetization shows a strong dependence on stress. This effect should have nondestructive testing applications suited for field inspection.
49 citations