Magnetoelastic Acoustic Emission Theory and Applications in Ferromagnetic Materials

The book presents theoretical and experimental studies to establish the relationship between volume jumps of the 90° domain wall in a ferromagnetic material and the magnitude of the half-space surface displacement caused by it. A method of evaluating the influence of the external magnetic field on the stress intensity factor at the tip of the crack-like defects in ferromagnets is discussed. The influence of hydrogen on the generation of magneto-elastic acoustic emission signals of ferromagnets is described. The features of magneto-elastic acoustic emission due to the presence of plastic deformation, structural changes, and volumetric damage in such structural materials are shown.

Some Concepts on Remagnetization of Ferromagnets.- Barkhausen Effect and Emission of Elastic Waves Under Remagnetization of Ferromagnet.- Models of MAE and Interaction of Magnetic Field with Cracks.- Models of Hydrogen Cracks Initiation as Sources of Elastic Waves Emission.- Estimation of Hydrogen Effect on Metals Fracture.- Determination of Magnetic Ductility and Residual Magnetization of Steels.- Methodology of Investigation the Hydrogen Influence on Ferromagnet.- Mathematical Models of MAE Signal and its Informative Parameters.- Evaluation of Electrolytically Absorbed Hydrogen by MAE Parameters.

Valentyn Skalskyi was born in the Rivne region, Ukraine, on June 25, 1954. He studied radio engineering at the Lviv Polytechnic Institute (1978). He received the Candidate of Sc. (PhD) and Doctor of Sc. (DSc) Degrees from the Karpenko Physico-Mechanical Institute of the NAS of Ukraine in 1993 and 2003 respectively, both in mechanics of a deformable solid. He holds the State scientific grades of professor (2009) in the diagnosis of materials and constructions.

Since 1980, Prof. Skalskyi is with the Karpenko Physico-Mechanical Institute of the National Academy of Sciences (NAS) of Ukraine. He holds the position of Vice-Director of this Institute since 2015. Also, since March 2015 he is a Member of the NAS of Ukraine.

His research interests include fracture mechanics, technical diagnostic and nondestructive testing, and the development of systems of digital signal processing. He has over 500 publications (35 books including) in scientific journals and conference proceedings. Currently, he is the editorial board member of the international journal Materials Science.

Prof. Skalskyi is an Honored Worker in the Science and Engineering of Ukraine, holds the State Prize of Ukraine for Science and Engineering, and two NASU Prizes for works for NDT methodology and its application based on acoustic emission.

Zinoviy Nazarchuk was born in Lviv, Ukraine, in 1952. He received the Candidate of Sc. (Ph.D.) and Doctor of Sc. Degrees from Kharkiv State University in 1982 and 1990 respectively, both in radio science. He holds the State scientific grades of the senior researcher (1988) and professor (1998) in theoretical and mathematical physics.

Since 1976, Prof. Nazarchuk is with the Karpenko Physico-Mechanical Institute of the National Academy of Sciences of Ukraine (NASU). He holds the positions of Vice-Director (1991-2014) and Director (since 2015) of this Institute. Also, since 2007 heis a member of the Presidium of NASU and head of the Western Scientific Center of NASU and the Ministry of Education and Science of Ukraine.

Prof. Nazarchuk is a Member of NASU (since 2006). He works in the field of material science, theoretical radio physics, and mathematical modeling. His principal area of research is the wave theory and applied mathematics. He has more than 370 publications (15 books including) in the field of the theory of material diagnostics, non-destructive testing, and numerical electromagnetics. Currently, he is the editor-in-chief of the international journal Materials Science and the periodical interbranch collection of scientific papers on Information Extraction and Processing.

Prof. Nazarchuk is an Honored Worker in the Science and Engineering of Ukraine and holds the State Prize of Ukraine for Science and Engineering and three NASU Prizes for works in the theory of physical fields and for NDT methodology and its application based on acoustic emission.