A method for manufacturing a metal ring laminate includes: performing an aging treatment on a metal ring laminate in which a plurality of metal rings made of maraging steel are laminated; and performing a nitriding treatment on the metal ring laminate that has been nitrided. Oxidizing treatment is performed after the aging treatment but before the nitriding treatment at a temperature equal to or higher than 350° C. and lower than an aging treatment temperature.

A method for manufacturing a metal ring laminate includes: performing an aging treatment on a metal ring laminate in which a plurality of metal rings made of maraging steel are laminated; and performing a nitriding treatment on the metal ring laminate that has been nitrided. Oxidizing treatment is performed after the aging treatment but before the nitriding treatment at a temperature equal to or higher than 350° C. and lower than an aging treatment temperature.

The present invention aims at providing an iron-nitrogen-based soft magnetic steel sheet having a saturation magnetic flux density higher than that of pure iron, a method for manufacturing the soft magnetic steel sheet, and a core and a dynamo-electric machine in which the soft magnetic steel sheet is used. The soft magnetic steel sheet according to the present invention includes C, N, and the balance of Fe and inevitable impurities and is comprised of an α phase, an α′ phase, an α″ phase, and a γ phase. The α phase serves as a main phase, a volume ratio of the α″ phase is 10% or more, and a volume ratio of the γ phase is 5% or less. The core according to the present invention includes a laminated body of the soft magnetic steel sheets.

The present invention aims at providing an iron-nitrogen-based soft magnetic steel sheet having a saturation magnetic flux density higher than that of pure iron, a method for manufacturing the soft magnetic steel sheet, and a core and a dynamo-electric machine in which the soft magnetic steel sheet is used. The soft magnetic steel sheet according to the present invention includes C, N, and the balance of Fe and inevitable impurities and is comprised of an α phase, an α′ phase, an α″ phase, and a γ phase. The α phase serves as a main phase, a volume ratio of the α″ phase is 10% or more, and a volume ratio of the γ phase is 5% or less. The core according to the present invention includes a laminated body of the soft magnetic steel sheets.

Artificial lift pump components such as couplings are disclosed, all having a body formed from a selected material, the body having an inner diameter and an outer diameter, a first surface treatment introducing carbon, nitrogen, boron into the material to form a first and hard layer, and a second layer defined as an deposited coating to the first layer that is also made of a carbon, nitrogen, or boron and is further characterized as being ceramic like (hard) and having a low-friction.

A dual phase magnetic component, along with methods of its formation, is provided. The dual phase magnetic component may include an intermixed first region and second region formed from a single material, with the first region having a magnetic area and a diffused metal therein, and with the second region having a non-magnetic area. The second region generally has greater than 0.1 weight % of nitrogen.

A grain oriented electrical steel sheet includes: a base steel sheet; a lower layer which is arranged in contact with the base steel sheet; and an insulation coating which is arranged in contact with the lower layer and which includes a phosphate and a colloidal silica as main components. The base steel sheet includes the predetermined chemical composition and includes a B compound whose major axis length is 1 to 20 μm and whose number density is 1×10 to 1×10.sup.6 pieces/mm.sup.3. The lower layer is a glass film which includes a forsterite as main component or an intermediate layer includes a silicon oxide as main component.

A grain oriented electrical steel sheet includes: a base steel sheet; a glass film which is arranged in contact with the base steel sheet; and an insulation coating which is arranged in contact with the glass film and which includes a phosphate and a colloidal silica as main components. The base steel sheet includes the predetermined chemical composition. A BN whose average particle size is 50 to 300 nm is included at a predetermined number density in a region which is from an interface between the glass film and the insulation coating till 5 μm toward the base steel sheet in a depth direction. A B emission intensity obtained inside the glass film is more than a B emission intensity obtained inside the base steel sheet, when a B emission intensity is measured from a surface of the insulation coating by a glow discharge emission spectroscopy.

A grain oriented electrical steel sheet includes: a base steel sheet; a glass film which is arranged in contact with the base steel sheet; and an insulation coating which is arranged in contact with the glass film and which includes a phosphate and a colloidal silica as main components. The base steel sheet includes the predetermined chemical composition. A BN whose average particle size is 50 to 300 nm is included at a predetermined number density in a region which is from an interface between the glass film and the insulation coating till 5 μm toward the base steel sheet in a depth direction. A B emission intensity obtained inside the glass film is more than a B emission intensity obtained inside the base steel sheet, when a B emission intensity is measured from a surface of the insulation coating by a glow discharge emission spectroscopy.

There is provided a precipitation hardening steel with the composition: C: 0.05-0.30 wt %, Ni: 3-9 wt %, Mo: 0.5-1.5 wt %, Al: 1-3 wt %, Cr: 2-14 wt %, V: 0.25-1.5 wt %, Co: 0-0.03 wt %, Mn: 0-0.5 wt %, Si: 0-0.3 wt %, and remaining part up to 100 wt % is Fe and impurity elements, with the additional proviso that the amounts of Al and Ni also fulfil Al=Ni/3±0.5 in wt %. There is the possibility to have very low amounts of cobalt, well below 0.01 wt %. The precipitation hardening steel displays, low segregation, high yield strength at elevated temperatures, high resistance against corrosion, and can also suitably be nitrided. The precipitation hardening steel is more economical to manufacture compared to steel according to the state of the art with the same strength at elevated temperatures.