Abstract: A hollow spherical flux source produces a uniform high-field in its central cavity. The sphere is comprised of a selected magnetic material whose magnetization is aximuthally symmetrical. The magnetic orientation (.alpha.) in the spherical permanent magnet shell is given by the equation:.alpha.=z.theta.where .theta. is the polar angle.

Abstract: Periodic permanent magnet structures comprise a plurality of azimuthally cumscribed sections of hollow spherical flux sources such that each flat face of said sections abuts one or more superconducting planar sheets. The superconducting sheets act as magnetic mirrors to complete the magnetic image of the sections. This produces a uniform high field in the central cavity(s). Each spherical section has an axial bore hole through its magnetic poles. The flux sources are arranged tangent to each other with the bore holes coaxially aligned to form a continuous channel through which charges particles may travel.

Abstract: A hollow hemispherical flux source produces a uniform high-field in its central cavity. The hemisphere is comprised of a selected magnetic material whose magnetization is azimuthally symmetrical. The magnetic orientation (.alpha.) in the hemispherical permanent magnet shell is given by the equation:.alpha.=2.theta.where .theta. is the polar angle. A planar plate of high saturation, high permeability material closes the open end of the hemisphere. An axial bore hole through the hemisphere and/or through the planar plate provides the requisite accessability.

Abstract: Periodic permanent magnet structures comprise a plurality of hollow spherl magnetic flux sources each of which produces a uniform high-field in its spherical central cavity. Each sphere has an axial bore hole through its magnetic poles. The spheres are disposed tangent to each other with the axial bore holes of the same coaxially aligned to form a continuous channel or path through which a beam of charged particles can travel.

Abstract: In the preferred embodiment a plurality of toroidally shaped magnets of slar size and configuraton are placed in a stack side-by-side in coaxial alignment. Alternate magnets in the stack are magnetized so that the magnetic dipole moment of each is oriented in the radial direction. An axial magnetized toroidal magnet is disposed between each pair of adjacent radially magnetized magnets. The magnetic orientation of the succesive toroidal magnets of the stack rotates continually in one direction in increments of 90.degree. or .pi./2 radians from the magnet at one end of the stack to that at the other end.

Abstract: Truncated clad magnetic structures producing a strong magnetic field within an interior working space and having minimal external flux leakage. Cladding magnets are added to structures which otherwise must be theoretically infinite. The cladding magnets, specially shaped so that their exterior surfaces are at zero magnetomotive potential, permit the use of truncated structures without loss of field strength or uniformity. Cladding formulas give approximate values which can be made more nearly exact by successive approximations in cladding thickness variations.

Abstract: A method and apparatus for the contactless, non-destructive measurement of Hall coefficient and resistivity of a piezoelectric semiconductor sample. The material to be tested is formed in a disk which is supported at its edge by a holder. The disc is free to vibrate. Two pairs of electrodes, placed above and below the sample, excite the sample into and beyond piezoelectric resonance. Then a magnetic field is applied to the sample and the sample again driven into and beyond resonance. Comparison between the performance of the disk before and after application of the magnetic field yields data from which Hall coefficient can be determined.

Abstract: Permanent magnet structures in several alternative forms are fabricated f multiplicities of permanent magnet segments of magnetic materials, preferably rare earth compounds, with the segments displaced radially from each other progressively along the structures elongate axes so as to produce a heliform magnetic field extending centrally in a passage through the structure.

Abstract: A magnetic circuit with a frustum-shaped magnet having a longitudinal bore nd circumscribed by a cladding magnet of varying radial thickness with a non-linear outer exterior surface. The cladding magnet is radially magnetized and the frustum-shaped magnet is axially magnetized, resulting in a constant magnetic potential along the non-linear outer exterior surface of the cladding magnet. A laterally uniform longitudinally increasing magnetic field is created within the bore.

Abstract: A magnetic circuit with a remanence varying cylindrical magnet having a b and a remanence varying cladding magnet circumscribing the cylindrical magnet creating a longitudinally increasing axial magnetic field within the bore. The cladding magnet has a radial magnetization transverse to the axial magnetization of the cylindrical magnet resulting in a constant magnetic potential along the outer exterior surface of the magnetic circuit.

Abstract: A magnetic device of permanent magnet materials for the control of linearly xtending annular cross-sectioned magnetic fields formed of two concentrically nesting magnetic tubular elements defining an annular space therebetween, and inner and outer cladding magnets radially disposed around the outer of said tubular elements and interiorly of the inner of said tubular elements, the cladding magnets being thicker at the end extremities and diminishing in thickness towards and to the plane of zero magnetic potential at or near the center line of the device measured along its longitudinal axis.

Abstract: A rare earth permanent magnetic apparatus for the containment and control thout any substantial loss of field flux comprising electro-deposited layers of rare earth magnetic material disposed and laid up around a ferrite center core element, the first or inner layer comprising a uniformly thick supply magnet to produce the magnetic field to be controlled, and the second or cladding magnet constituting a layer of diminishing thickness from the outboard ends of the device towards and to the plane of zero magnetic potential at or near the middle of the device.

Abstract: A magnetic cladding device having a constant exterior magnetic potential al to a magnetic potential at a point between either end of an active magnet for enhancing the active magnet's field and reducing magnetic field leakage comprising a magnetic cladding circumscribing an active magnet and having a magnetic axis transverse to that of the active magnet.

Abstract: A method and apparatus for pressing magnetic powder in a toroidal-shape we in a radial magnetic field. A magnetic flux is produced and carried by a die rod through the axial center of toroidally-shaped magnetic powder. An annular portion coaxially surrounding the die rod and magnetic powder is connected to a yoke member which carries the magnetic flux back to the magnetic flux producing means. This completes the magnetic circuit, and creates a radial magnetic field across the toroidally-shaped magnetic powder between the die rod and the annular portion. This radial magnetic field aligns the granules of the toroidally shaped magnetic powder during pressing.

Abstract: Magnetic alloys of the general formula Sm.sub.2 Cu.sub.1.6 Zr.sub.0.16 Fe.sub.3.3 Co.sub.12-x M.sub.x are provided wherein M is Mn or Cr and wherein x is a value greater than zero and less than 2.1.

Abstract: Compounds of the general formula Sm.sub.2-x RE.sub.x Co.sub.17-y Mn.sub.y are provided wherein RE is a rare earth element selected from the group consisting of erbium, dysprosium and gadolinium wherein x has a value greater than zero and less than 0.7 and wherein y has a value less than 2.1. The compounds are suitable for use as permanent magnet material in microwave/millimeter-wave traveling wave tubes (TWT's).

Abstract: The reversible temperature coefficient of magnetization of a permanent magnet alloy is lowered by (a) heating the alloy at about 1200 degrees C. for 2 hours, (b) quenching the alloy in ice water, (c) heating the alloy at about 850 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for one hour, (g) lowering the temperature to about 400 degrees C. and heating for four hours, and (h) lowering the temperature to about 280 degrees C. and heating for 12 hours. The method is particularly effective in lowering the reversible temperature coefficient of magnetization of the permanent magnet alloy Sm.sub.2 Cu.sub.1.6 Zr.sub.0.16 Fe.sub.3.3 Co.sub.12.

Abstract: A method of making a permanent magnet magic ring structure. An annular cyder made from a magnetically hard material is uniformly magnetized in a direction perpendicular to its major axis. The cylinder is cut into eight or sixteen or 32 or more segments. Various segments are interchanged with other segments to produce a magic ring which has an intense uniform magnetic field within a central working space.