Abstract: An improved process for forming high quality ferrite magnets utilizes relatively coarsely ground magnetic materials. The process includes pre-milling a blended and calcined magnetic material to about 0.7-1.2 microns, pressing the blend into a preform shape in the presence of an orienting magnetic field, granulating the preformed material, pre-sintering the granules short of complete sintering, milling the granules to a coarse size of about 1-2 microns, forming the milled blend into desired forms in the presence of an orienting magnetic field, sintering the pressed material, and optionally machining the sintered material.

Abstract: A method for applying a phosphate conversion coating atop an iron-rare earth-boron alloy not normally susceptible to phosphating includes the step of applying a compatible metal layer to the alloy substrate before phosphatizing. The metal layer can be an alloy or an elemental metal, preferably zinc or nickel, and optimally nickel. The rare earth in the alloy is optimally neodymium. Any of the conventionally known metal coating and phosphating procedures can be generally employed in the method of the invention. An article having an iron-rare earth-boron substrate and a phosphate conversion coating atop the substrate, preferably formed as the product of the disclosed method, is also disclosed.

Abstract: A linear electric motor having an oscillating linear armature disposed in proximity to a stationary stator and provided with an output member which can be directly coupled to a load. A power supply and control circuit is provided for matching the power input to the linear motor according to changing load conditions at the output.

Abstract: The rotor or stator of an electro-magnetic machine, such as an electric motor, having permanent magnets is provided with auxiliary permanent magnets which are relatively positionable to provide an external magnetic flux path during normal operation of the machine and an internal magnetic flux path to enable the rotor to be readily separated from the stator for the purpose of maintenance or repair work. The invention also contemplates, for example, fine speed calibration, through variation of the intensity of a magnetic field during running of electro-magnetic machines such as DC motors.

Abstract: An electromagnetic chuck power supply and control comprising a magnetic amplifier consisting of a saturable reactor supplying DC power at its output across the electromagnet coils of the electromagnetic chuck. A controllably variable DC current is supplied across the control winding of the magnetic amplifier such that the DC power at the output of the magnetic amplifier is inversely proportional to the DC current flow through the control winding. Variable workpiece holding power is thus obtained at the electromagnetic chuck. At full control current flow, the electromagnetic chuck has no holding power except that due to the residual magnetization of the workpiece. In the event of complete failure of the control current circuit, maximum holding force is applied by the chuck to the workpiece.