Abstract: Ferrite materials are disclosed, comprising, as main components, an amount of iron component ranging from 51.0 to 59.0 mole percent calculated as Fe2O3, an amount of manganese component ranging from 38.0 to 47.0 mole percent calculated as MnO, and an amount of zinc component ranging from 1.0 to 3.0 mole percent calculated as ZnO. Embodiments provided herein also include, as minor components, an amount of calcium component ranging from 0.010 to 0.060 weight percent calculated as CaO, an amount of silicon component ranging from 0.005 to 0.040 weight percent calculated as SiO2, and, optionally, an amount of niobium component ranging up to 0.040 weight percent calculated as Nb2O5, an amount of zirconium component ranging up to 0.050 weight percent calculated as ZrO2, and an amount of tantalum component ranging up to 0.060 weight percent calculated as Ta2O5. Methods of forming the ferrite materials and products formed therefrom are also disclosed herein.

Abstract: Ferrite materials, methods of forming the same, and products formed therefrom are disclosed, comprising, as main components, an iron oxide ranging from 55.5 to 58.0 mole percent calculated as Fe2O3, an amount of manganese oxide ranging from 38.0 to 41.0 mole percent calculated as MnO, and an amount of zinc oxide ranging from 3.3 to 4.7 mole percent calculated as ZnO. The present invention also includes, as minor components, an amount of calcium oxide ranging from 0.030 to 0.100 weight percent calculated as CaO, an amount of silicon oxide ranging from 0.015 to 0.040 weight percent calculated as SiO2, and an amount of niobium oxide ranging from 0.010 to 0.030 weight percent calculated as Nb2O5.

Abstract: New ferrite tuning assemblies are disclosed in which a unitary ferrite shaft is covered with a nonmagnetic material to provide a peripheral working surface for coacting with unitary helical thread means in the central opening of a core element to provide axial movement, for air gap adjustment purposes, by cutting and/or deforming at least a portion of the peripheral working surface of the tuning member. Various longitudinal and transverse cross-sectional configurations for the integral male tuning member are made available by the fabrication and assembly methods taught; assembly of inductance-tunable ferrite devices is facilitated by enabling insertion of a male tuning member into the central opening of either core element in an assembly and tuning from either longitudinal end of the aligned central openings.

Abstract: New fabricating methods and products are disclosed for manufacture and assembly of tunable-inductance magnetically-soft ferrite core assemblies. Pot core type elements are pressure molded from ferrimagnetic particles having residual reactivity; unitary helical threads are tapped in central openings of compacted core elements while in the green state; subsequent heat treatment converts the green compact to a ceramic. Use of a shrink tap provides compatibility of the unitary threads with the pre-threaded male adjustment members of the prior practice. A new assembly enables use of identical core half sections; provision is made for support at one or both longitudinal ends of the male tuning member.

Abstract: New ferrite pot core type products and fabrication methods are disclosed for production and assembly of tunable-inductance magnetically-soft ferrite devices. Unitary helical threads formed within the central opening of a ferrite pot core element provide controlled axial movement of a non-threaded male tuning member, carrying a ferrite rod, to adjust the air gap between spaced center posts of an assembled pair of pot core elements. Thread matching and registry requirements are eliminated by such unitary thread means which present either helical path die means, for cutting threads in a cylindrical nonmagnetic portion of a male tuning member or, circumferentially continuous helical threads, which deform nonmagnetic protrusions uniformly distributed about the periphery of a noncircular cross section nonmagnetic portion of a male tuning member during rotation of a male tuning member within a core element central opening.