The relationship between microstructure and magnetic properties of Si-containing permalloy strips fabricated by melt drag casting

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 449; pp. 444 - 447
• Main Authors: Lim, K.M., Park, S.Y., Namkung, J., Kim, M.C., Park, C.G.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 25-03-2007; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Domain effects, magnetization curves, and hysteresis; Exact sciences and technology; Magnetic properties and materials; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Melt drag casting; Ni 3Fe ordered phase; Permalloys; Physics; Si effects; Melt drag casting; Permalloys; Ni 3Fe ordered phase; Si effects; Grain size; Nickel base alloys; Annealing; Iron alloys; Ni3Fe ordered phase; Silicon additions; Cold rolling; Optical microscopy; Transmission electron microscopy; Magnetic permeability; Magnetic anisotropy; Property structure relationship; Strip casting; Microstructure; Transition element alloys; Magnetic properties
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.02.449

The effects of Si addition on microstructure and magnetic properties of permalloy strips fabricated by the melt drag casting method were investigated. Permalloy strips with 200
mm width were successfully fabricated by melt drag casting followed by homogenizing, cold rolling and annealing. In order to understand the relationship between microstructure and magnetic properties, we measured permeability and analyzed microstructure as a function of Si content by optical microscopy, X-ray diffraction and transmission electron microscopy. The effective permeability went through a maximum value in 2
at.% Si added permalloy strips and then decreased with increasing Si content. Increasing Si content enlarged grain size, which resulted in improvement of permeability. Permalloy strips with 5
at.% Si, however, showed drastically reduced permeability than that of 2
at.% Si added ones notwithstanding their coarse grain size and little oxide inclusion. The degradation of permeability in over-added Si above 2
at.% could be explained by formation of Ni
3Fe ordered phase, which increase magneto-crystalline anisotropy.