A method for improving the corrosion resistance of NdFeB materials is provided. The method includes in-situ growing a layer of oxide, nitride, or oxynitride on the surface of NdFeB magnet correspondingly by performing at least one of an oxidation treatment and a nitridation treatment at low temperature in a range of 200?400? C., thereby significantly improving the corrosion resistance of the magnet. The method is simple to operate, low-cost, green, safe, and efficient. Depending on the parameters of the low-temperature oxidation and/or nitridation treatment, the thickness of the oxide, nitride, or oxynitride layer is adjustable from 10 nm to 100 ?m, which can improve the corrosion resistance of the magnet while maintaining excellent magnetic properties. Moreover, the thin surface layer is in-situ grown on the NdFeB substrate, which is strong and stable over a long service period and can be applied for mass production.

The present disclosure relates to a forming method for producing a composite part for an operating member, the method comprising the steps: disposing at least one permanent magnet in an injection-molding tool, which defines a mold cavity, and a heat-conducting reinforcement, which extends along the permanent magnet and is in touching contact with the injection-molding tool, in each case at a predefined position of the mold cavity; overmolding the permanent magnet with molding material by introducing molding material into the mold cavity; forming the composite part having the at least one permanent magnet, the heat-conducting reinforcement and the molding material.

This invention is directed to a corrosion resistant permanent magnet, to a method for producing a corrosion resistant permanent magnet, and to an intravascular blood pump comprising the magnet. The magnet is corrosion resistant due to a composite coating comprising a metal layer, optionally a metal oxide layer, a layer formed from poly(2-chloro-p-xylylene), and a linker layer between the metal oxide layer and the poly(2-chloro-p-xylylene) layer.

A process is provided for the production of rare earth magnets comprising the steps of exposing a rare earth alloy to hydrogen gas at an elevated temperature so as to effect hydrogenation and disproportionation of the alloy, mechanically processing the disproportionated alloy, and degassing the processed alloy so as to effect hydrogen desorption and recombination of the alloy. The process of the invention finds use in the production and shaping of rare earth magnets, and may be particularly applicable to the production of thin magnetic sheets.

Manufacturing techniques for producing thin magnetic elements are designed to accommodate the mechanical properties of sintered magnetic substrates. One of the manufacturing processes involves cutting a magnetizable substrate into a number of slices and adhesively coupling the slices to a sheet that can take the form of a layer of grinding tape. After concurrently grinding a first surface of each of the slices, the slices are flipped over so that the first surface of each slice is attached to another layer of grinding tape. A second surface of each of the slices is then ground until a desired thickness is achieved. Subsequent to the grinding, dicing operations can be applied to the slices to produce magnets having a desired length and width.

A sintered Nd base magnet segment has a coercive force high at the periphery and lower toward the inside. A method for preparing the magnet includes the steps of: (a) providing a sintered Nd base magnet block having surfaces and a magnetization direction, (b) coating the surfaces of the magnet block excluding the surface perpendicular to the magnetization direction with a Dy or Tb oxide powder, a Dy or Tb fluoride powder, or a Dy or Tb-containing alloy powder, (c) treating the coated block at a high temperature for causing Dy or Tb to diffuse into the block, and (d) cutting the block in a plane perpendicular to the magnetization direction into a magnet segment having a coercive force distribution on the cut section that the coercive force is high at the periphery and lower toward the inside and a constant coercive force distribution in the magnetization direction.

A method for manufacturing a NdFeB rare earth permanent magnetic device with composite plating includes steps of: firstly melting alloy, casting the alloy in a melted state onto a rotation copper roller with a water cooling function, so as to be cooled for forming alloy flakes; hydrogen decrepitating; mixing after hydrogen decrepitating; jet milling after mixing; mixing under nitrogen protection before molding in a nitrogen protection magnetic field pressing machine, and then packing in a protection tank before being moved out of the protection tank and isostatic pressing; sintering in a sintering device and aging for forming a NdFeB rare earth permanent magnet; machining for forming a NdFeB rare earth permanent magnetic device; and plating the NdFeB rare earth permanent magnetic device, wherein three layers of plated films are formed.

A method for recycling a rare earth magnet is described. The rare earth magnet has a film containing Ni on the surface thereof, and the method involves immersing the rare earth magnet in a stripping solution containing a derivative of nitrobenzene, ethylenediamine, and ammonia. This strips the Ni on the surface of the rare earth magnet without deteriorating the characteristics of the rare earth magnet, thereby improving its product yield.

Provided is a rare earth magnet, on the surface of which a coating film of an ultraviolet cured resin is formed by covering the surface of the rare earth magnet with an ultraviolet curable resin composition and subsequently curing the ultraviolet curable resin composition by irradiating the ultraviolet curable resin composition with ultraviolet light. With respect to this rare earth magnet, the coating film is formed by a method which comprises: a step for having droplets of the ultraviolet curable resin composition adhere to the rare earth magnet surface by ejecting the droplets of the ultraviolet curable resin composition from a tip of a head by an inkjet method wherein droplets are ejected from a head; and a step for curing the ultraviolet curable resin composition by irradiating the ultraviolet curable resin composition adhering to the rare earth magnet surface with ultraviolet light.

A magnetic article with a corrosion resistant barrier formed from a poly (tetrafluoro-p-xylene) conformal coating or from a parylene conformal coating having a melting point of at least about 430 C. and a moisture vapor transmission less than about 0.5 g-mm/m.sup.2/day at 90% RH and 37 C., the conformal coating being covered with a polysulfone thermoplastic overlayer.