Abstract: A magnetic top stick for use at the opening portion of a core slot of an electromagnetic device includes a group of magnetically anisotropic members arranged in a substantially non-magnetic body adapted to fit snugly within the core slot. The magnetic properties of the group of members combine to provide the top stick with an overall high magnetic permeability in the depth direction of the core slot and overall low magnetic permeabilities in the width and longitudinal directions of the core slot. A convenient method of manufacturing the top stick includes first forming magnetically anisotropic sheets by cold rolling and annealing, then laminating and heat processing the sheets with B stage materials to generate a unitary laminated structure. The unitary laminated structure is sectioned into multiple magnetic flux bars which are in turn disposed in the non-magnetic body forming the top stick.

Abstract: The present invention relates to a novel process for producing silicon and/or aluminum containing iron alloy product as well as the material produced from same in either sheet or bulk structure form for electromagnetic circuit application. The process entails modifying an iron feedstock containing less than about 2.5 wt % silicon, aluminum or a combination thereof. The process further consists of diffusion of silicon or silicon and aluminum or aluminum into an iron feedstock by a pack diffusion or a chemical vapor deposition method in which the iron feedstock is heated to a temperature at which diffusion occurs in the presence of a pack containing silicon and/or aluminum sources, a reducing agent, a catalyst, and a filler, or in the presence of a flowing gas stream containing a volatile silicon compound. The resulting iron alloy product, which has a silicon content in the range of 0.