Abstract: In order to provide a separator for fuel cells, or a current collecting member for fuel cells, which has low contact resistance, excellent corrosion resistance and which can be economically manufactured, and a manufacturing method thereof, this separator 110 for fuel cells comprises a substrate 11 having iron or aluminum as the main component, a gas barrier film 12 formed directly on said substrate 11 and having excellent corrosion resistance, and a conductive resin film 13 formed on the gas barrier film 12 and containing a conductive ceramic or graphite particles having a particle diameter of 1-20 ?m.

Abstract: A metal ring of a transmission belt in a belt-type continuously variable transmission. A first nitrided layer formed in a main surface of the metal ring, and a second nitrided layer formed in an end surface of the metal ring are included. A thickness of the second nitrided layer is smaller than a thickness of the first nitrided layer, and surface hardness of the end surface is higher than surface hardness of the main surface. Even though the second nitrided layer in the end part is thin, the surface hardness of the end surface is high. Therefore, it is possible to restrain fatigue fracture starting from an end part, and it is also possible to restrain deterioration of abrasion resistance of the end surface.

Abstract: A low alloy steel is heated to a temperature ranging from 550 to 620° C., and high KN and low KN value processes are performed for a total process time of A: 1.5 to 10 hours. In the high KN value process, a nitriding potential KNX given by Formula (1): 0.15 to 1.50, the average KNX value KNXave: 0.30 to 0.80, and the process time is X in hours. In the low KN value process, which is performed after the high KN value process, a nitriding potential KNY given by Formula (1): 0.02 to 0.25, the average KNY value KNYave: 0.03 to 0.20, and the process time is Y in hours. Average nitriding potential value KNave determined by Formula (2) ranges from 0.07 to 0.30. KNi=(NH3 partial pressure)/(H2 partial pressure)3/2]??(1) KNave=(X×KNXave+Y×KNYave)/A??(2) where i is X or Y.

Abstract: A hydrophilic-hydrophobic transformable composite film is disclosed, which has an iron-containing substrate; a silicon-containing layer formed on the iron-containing substrate; and a titanium oxide layer formed on the silicon-containing layer. The hydrophilic-hydrophobic transformable composite film uses UV-light to switch its hydrophilic and hydrophobic property. Also, a method of fabricating the above composite film is disclosed. According to the present invention, an anatase oxide layer can be obtained from the sol-gel techniques, in which the particle size of the titanium dioxide is controlled and a modified surface coating with evident photo-catalyticity is achieved.

Abstract: A piston ring for at least one of a piston of an internal combustion engine and a compressor may include at least one substantially annular metallic base having a nitrided layer. The base may include at least one chamfer and at least one outer surface that maintains contact with a layer of lubricating oil. The nitrided layer may exhibit a substantially constant thickness over at least one surface of the base and the at least one chamfer. The nitrided layer may include a nitrided diffusion layer that maintains direct contact with the layer of lubricating oil and has a residual tension ranging from +100 megapascal to ?100 megapascal.

Abstract: A nitrided steel member including an iron nitride compound layer formed on a surface of a steel member having predetermined components, wherein: in X-ray diffraction peak intensity IFe4N (111) of a (111) crystal plane of Fe4N and X-ray diffraction peak intensity IFe3N (111) of a (111) crystal plane of Fe3N, which are measured on a surface of the nitrided steel member by X-ray diffraction, an intensity ratio expressed by IFe4N (111)/{IFe4N (111)+IFe3N (111)} is 0.5 or more; Vickers hardness of the iron nitride compound layer is 900 or less, Vickers hardness of a base metal immediately under the iron nitride compound layer is 700 or more, and a difference between the Vickers hardness of the iron nitride compound layer and the Vickers hardness of the base metal is 150 or less; and a thickness of the iron nitride compound layer is 2 to 17 ?m.

Abstract: A steel which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or more of Cr: 0.05 to 1.5%, V: 0.05 to 0.2%, Mo: 0.05 to 0.4%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel being formed with (a) a nitrided layer having a certain thickness range and a nitrogen concentration higher than the nitrogen concentration of the steel by 0.02 mass % or more and (b) a low carbon region having a certain depth range from the surface of the steel and having a carbon concentration of 0.9 time or less the carbon concentration of the steel.

Abstract: A stainless steel separator for fuel cells and a method of manufacturing the same are disclosed. The method includes preparing a stainless steel sheet as a matrix, performing surface modification on a surface of the stainless steel sheet to form a Cr-rich passive film having a comparatively increased amount of Cr in a superficial layer of the stainless steel sheet by decreasing an amount of Fe in the superficial layer of the stainless steel sheet, and forming a coating layer on the surface of the surface-modified stainless steel sheet. The coating layer is one selected from a metal nitride layer (MNx), a metal/metal nitride layer (M/MNx), a metal carbide layer (MCy), and a metal boride layer (MBz) (where 0.5?x?1, 0.42?y?1, 0.5?z?2).

Abstract: Disclosed are a method for adjusting the pore size of a porous metal material and the pore structure of a porous metal material. The method comprises: permeating at least one element into the surface of the pores of the material to generate a permeated layer on the surface of the pores, so that the average pore size of the porous material is reduced to within a certain range, thus obtaining a pore structure of the porous metal material having the pores distributed on the surface of the material and the permeated layer provided on the surface of the pores.

Abstract: A hand-held work implement having a tool has a braking device for the tool that includes a brake band which wraps around a brake drum. The brake band and the brake drum undergo friction as they move relative to one another during braking. At least one of the band or drum comprises an austenitic steel, a duplex steel, super duplex steel, a nickel-base alloy or a cobalt-base alloy and has a base body and a marginal layer. The hardness of the marginal layer is approximately 150% to approximately 600% of the hardness of the base body and the carbide proportion in the marginal layer is less than approximately 0.5% by weight. A process for production of the foregoing includes diffusing carbon and/or nitrogen into a marginal layer at a temperature of less than 500° C.

Abstract: The present invention provides ferromagnetic iron nitride particles, in particular, in the form of fine particles, and a process for producing the ferromagnetic iron nitride particles. The present invention relates to a process for producing ferromagnetic iron nitride particles, comprising the steps of mixing metallic iron obtained by mixing at least one compound selected from the group consisting of a metal hydride, a metal halide and a metal borohydride with an iron compound, and then subjecting the obtained mixture to heat treatment, with a nitrogen-containing compound; and then subjecting the resulting mixture to heat treatment, in which a reduction step and a nitridation step of the iron compound are conducted in the same step, and the at least one compound selected from the group consisting of a metal hydride, a metal halide and a metal borohydride is used as a reducing agent in the reduction step, whereas the nitrogen-containing compound is used as a nitrogen source in the nitridation step.

Abstract: A roller bearing having two cooperating rolling parts of which one is of ceramic and the other of a steel. The steel part is of such structure and/or material and/or is so produced to cause residual compressive stresses to form beneath the contact surface of the steel part, at least in a load-free state, down to a depth.

Abstract: The present invention provides spring use heat treated steel which is cold coiled, can achieve both sufficient atmospheric strength and coilability, has a tensile strength of 2000 MPa or more, and can improve the performance as a spring by heat treatment after spring fabrication, that is, high strength spring-use heat treated steel characterized by containing, by mass %, C: 0.45 to 0.9%, Si: 1.7 to 3.0%, and Mn: 0.1 to 2.0%, restricting N: to 0.007% or less, having a balance of Fe and unavoidable impurities, and satisfying, in terms of the analyzed value of the extracted residue after heat treatment, [amount of Fe in residue on 0.2 ?m filter/[steel electrolysis amount]×100?1.1.

Abstract: A method of activating an article of passive ferrous or non-ferrous metal by heating at least one compound containing nitrogen and carbon, wherein the article is treated with gaseous species derived from the compound. The activated article can be subsequently carburized, nitrided or nitrocarburized in shorter time at lower temperature and resulting superior mechanical properties compared with non-activated articles and even articles of stainless steel, nickel alloy, cobalt alloy or titanium based material can be carburized, nitrided or nitrocarburized.

Abstract: In a method for manufacturing a ferritic stainless steel product, a ferritic stainless steel object is heated in an inert gas atmosphere including nitrogen gas in a heating furnace at a nitriding temperature higher than or equal to a transformation temperature so as to form a nitrided layer on a surface of the ferritic stainless steel object. Moreover, the nitriding temperature is set lower than 1100° C. during the heating. The heating of the ferritic stainless steel object is performed in a state where a solid carbon exists inside the heating furnace.

Abstract: In a method of manufacturing a grain-oriented electrical steel sheet including a nitriding treatment (step S7) and adopting so-called “low-temperature slab heating”, the finish temperature of finish rolling in hot rolling (step S2) is set to 950° C. or below, the cooling is started within 2 seconds after completion of the finish rolling, and a steel strip is coiled at 700° C. or below. The cooling rate over the duration from the end of finish rolling to the start of coiling is set to 10° C./sec or above. In annealing (step S3) of the hot-rolled steel strip, the heating rate in the temperature range from 800° C. to 1000° C. is set to 5° C./sec or above.

Abstract: A method for treating a steel bearing component includes subjecting the steel bearing component to a scouring treatment to impart compressive residual stress to a surface region thereof and subsequently nitriding the steel bearing component 1. The resulting steel bearing component exhibits a nitrided case depth of about 0.002-0.014 inches and a compressive residual stress value greater than ?120 ksi is achieved at a depth of 0.002 inches and ?20 ksi to a minimum depth of 0.010?. The steel bearing component may be a race and/or a rolling element, such as a ball.

Abstract: The present invention comprises a process for nitriding martensitic stainless steel and the alloy produced thereby comprising heating a stainless steel alloy to a temperature of from about 900° F. (480° C.) to about 2500° F. (1370° C.) in a vacuum furnace in the presence of hydrogen or argon gas in order to clean the surface. After the hydrogen or argon gas is removed from the chamber, nitrogen gas, or a different nitrogen gas derivative is injected into said furnace as a pulsed injection at a partial pressure of from about 500 torr to about 1000 torr. The steel is nitrogen alloyed at a temperature of from about 1400° F. (760° C.) to about 2200° F. (1205° C.) and then quickly quenched at ambient temperature. Preferably, after a sufficient period of time, the temperature is raised a second time from about 900° F. (480° C.) to about 2500° F. (1370° C.) prior to cooling the final product.

Abstract: To provide a metal ring excellent in durability by reducing decrease in margin of strength and concentration of tensile stress at its both widthwise end portions and to efficiently realize a production method of the same, a metal ring is formed in an endless band-like body having a nitride layer on its surface portion and constituting part of a metal belt of a belt type continuously variable transmission, the nitride layer being constituted by a first nitride layer portion positioned on an outer circumferential side, a second nitride layer portion positioned on an inner circumferential side, and third nitride layer portions positioned on both widthwise end sides, and the layer thicknesses of the third nitride layer portions being smaller than either one of the layer thicknesses of the first nitride layer portion and the second nitride layer portion.

Abstract: Provided are a method for producing powder for a magnet, and methods for producing a powder compact, a rare-earth-iron-based alloy material, and a rare-earth-iron-nitrogen-based alloy material. Magnetic particles constituting the powder each have a texture in which grains of a phase of a hydride of a rare-earth element are dispersed in a phase of an iron-containing material. The uniform presence of the phase of the iron-containing material in each magnetic particle results in powder having excellent formability, thereby providing a powder compact having high relative density. The powder is produced by heat-treating rare-earth-iron-based alloy powder in a hydrogen atmosphere to separate the rare-earth element and the iron-containing material and then forming a hydride of the rare-earth element. The powder is compacted. The powder compact is heat-treated in vacuum to form a rare-earth-iron-based alloy material.

Abstract: To provide a steel product excelling in both corrosion resistance and adhesion. A steel product having a nitride layer and a nitrogen diffused layer formed on the surface of a steel base material is provided. The nitride layer includes a first compound layer formed on a nitrogen diffused layer side and a second compound layer formed on a surface side of the first compound layer. The first compound layer has an ?-structure mainly made of Fe3N, and the second compound layer has a higher nitrogen concentration than the first compound layer and has a concavoconvex formed on the surface thereof. Thus, the nitride layer having excellent adhesion, an extremely small carbon containing amount, and high corrosion resistance can be formed.

Abstract: The invention relates to a crankshaft member having high fatigue strength and good bending correctability, and its method of manufacture. The steel made crankshaft member mainly consists of a two-phase structure of ferrite and perlite. The steel includes C, Ni, Mn, and Cr as required elements and Si, Cu, Mo, Ti, V, Nb, Ca, and S as optional elements that may be included, in the amounts of C within the range of 0.20 to 0.50 wt %, Si within the range of 0 to 0.6 wt %, Mn within the range of 0.5 to 1.5 wt %, Cu within the range of 0 to 0.7 wt %, Ni within the range of 0.05 to 1.5 wt %, Cr within the range of 0.05 to 0.45 wt %, and Mo within the range of 0 to 0.5 wt % to satisfy the condition 115?70C+8Si+23Mn+11Cu+128Cr+83Mo?50. A portion of the member surface is provided at least with a hard nitride layer having an average hardness within the range of 300 to 450 HV. Lamellar spacing of the perlite is 0.3 ?m or less.

Abstract: A flat steel product, intended to be formed into a component by hot press forming and having a base made of steel, onto which a metal anti-corrosion coating of a Zn or a Zn alloy is applied. A separate finishing coat is applied to at least one of the free surfaces of the flat steel product. The finishing coat includes at least one base metal compound (oxide, nitride, sulphide, sulphate, carbide, carbonate, fluoride, hydrate, hydroxide, or phosphate). Also, a method enabling the production of a flat steel product of this kind.

Abstract: The invention relates to a method for method for formation of expanded austenite and/or expanded martensite by solution hardening of a cold deformed workpiece of a passive alloy, which method comprises a first step of dissolving at least nitrogen in the workpiece at a temperature T1, which is higher than the solubility temperature for carbide and/or nitride and lower than the melting point of the passive alloy, and a subsequent second step of dissolving nitrogen and/or carbon in the work piece at a temperature T2, which is lower than the temperature at which carbides and/or nitrides form in the passive alloy. The invention further relates to a member, such as a lock washer for securing bolts or nuts prepared using the method.

Abstract: A steel piston ring and a steel cylinder liner are described which comprise as the main body a steel composition which has good nitridability. The steel composition consists of the following elements: 0-0.5 weight % B, 0.5-1.2 weight % C, 4.0-20.0 weight % Cr, 0-2.0 weight % Cu, 45.30-91.25 weight % Fe, 0.1-3.0 weight % Mn, 0.1-3.0 weight % Mo, 0-0.05 weight % Nb, 2.0-12.0 weight % Ni, 0-0.1 weight % P, 0-0.05 weight % Pb, 0-0.05 weight % S, 2.0-10.0 weight % Si, 0-0.05 weight % Sn, 0.05-2.0 weight % V, 0-0.2 weight % Ti and 0-0.5 weight % W. The steel piston ring and the steel cylinder liner can be manufactured in a casting process using the machinery and technology employed for the manufacture of cast iron parts.

Abstract: The present invention relates to ferromagnetic particles capable of exhibiting a high purity and excellent magnetic properties from the industrial viewpoints and a process for producing the ferromagnetic particles, and also provides an anisotropic magnet, a bonded magnet and a compacted magnet which are obtained by using the ferromagnetic particles.

Abstract: The present invention provides a nitrided steel member and manufacturing method thereof. the nitrided steel member including: an iron nitride compound layer formed on a surface of a steel member made of carbon steel for machine structural use or alloy steel for machine structural use, in which with regard to X-ray diffraction peak intensity IFe4N (111) of the (111) crystal plane of Fe4N and X-ray diffraction peak intensity IFe3N (111) of the (111) crystal plane of Fe3N obtained by measuring a surface of the nitrided steel member by X-ray diffraction, an intensity ratio represented by IFe4N(111)/{IFe4N (111)+IFe3N (111)} is 0.5 or more, and a thickness of the iron nitride compound layer is 2 to 17 ?m.

Abstract: A number of variations may include a brake rotor having a surface oxide layer and methods of making the same.

Abstract: A biocompatible material is made of a rust-resistant, alloyed stainless steel which is configured with at least one martensitic surface layer which is formed by a heat treatment with nitrogen case hardening and subsequent cooling. The surface layer, orthogonally to the surface into the sample interior, displaying a virtually linear course of the accompanying hardening and being achieved by a complete phase change (so-called austenitising) in the structural state from ferrite via austenite to martensite. In addition, the biocompatible material is in contact preferably indirectly or directly with the human body, no reactions and/or sensitivity problems being able to occur even in permanent use as a result of its absolute freedom from nickel.

Abstract: A process for forming an outer diffusion surface layer on a metal substrate or member includes in a first activation stage of an inert particulate refractory material and a metal based material including metals and metal halides. An inert gas and hydrogen halide gas is introduced into the inert particulate refractory material and the metal based material to activate an outer surface of the metal based material. The metal substrate is pretreated to form a diffusion zone extending inwardly from the outer surface of the metal substrate having nitrogen forming an inner diffusion zone and an outer compound or white layer of an iron nitride, an iron carbide or an iron carbonitride compound without an oxide layer. A subsequent diffusion stage treats the metal substrate in an inert gas, in the absence of hydrogen halide gas to form the diffusion surface layer on the metal substrate.

Abstract: The present invention relates to a method for manufacturing an implant, in particular an intraluminal endoprosthesis, having a body containing metallic material, preferably iron. For controlling the degradation of the implant the method includes the following steps: (a) providing a first part of the implant body; and (b) performing heat treatment which alters the carbon content and/or the boron content and/or the nitrogen content in the structure of a near-surface boundary layer in the first part of the implant body in such a way that strain on the lattice or a lattice transformation, optionally following a subsequent mechanical load, is achieved in the near-surface boundary layer. Such an implant is also described.

Abstract: A novel FeMnAlC alloy, comprising 23˜34 wt. % Mn, 6˜12 wt. % Al, and 1.4˜2.2 wt. % C with the balance being Fe, is disclosed. The as-quenched alloy contains an extremely high density of nano-sized (Fe,Mn)3AlCx carbides (??-carbides) formed within austenite matrix by spinodal decomposition during quenching. With almost equivalent elongation, the yield strength of the present alloys after aging is about 30% higher than that of the optimally aged FeMnAlC (C?1.3 wt. %) alloy systems disclosed in prior arts. Moreover, the as-quenched alloy is directly nitrided at 450˜550° C., the resultant surface microhardness and corrosion resistance in 3.5% NaCl solution are far superior to those obtained previously for the optimally nitrided commercial alloy steels and stainless steels, presumably due to the formation of a nitrided layer consisting predominantly of AlN.

Abstract: The invention relates to dining and/or serving cutlery made of a steel material which is formed from a ferritic core with an essentially martensitic boundary layer. In the dining and/or serving cutlery of the invention, the surface hardness of the boundary layer, determined according to the hardness test according to Vickers HV 3, is thereby greater by 30 to 300% than the lowest hardness of the core, likewise measured according to Vickers HV 3.

Abstract: Provided is a method of treating a metal surface, which can improve surface properties of a target metal, such as surface hardness and wear resistance in a simple manner and at low cost using very simple equipment alone, and which can prevent the deterioration of the metal to create high added value. The present invention is comprised of a method of treating a metal surface, characterized in that: heat-treating a target metal (10) to be surface-modified in nitrogen gas atmosphere (S), in such a state where the target metal (10) is buried in a carbon source powder (12) comprising a carbon powder and a powder of iron or an iron alloy mainly comprising iron and containing carbon, whereby the surface of the target metal (10) is at least nitrided or nitrogen-absorbed to modify the surface.

Abstract: In a method for coating steel strips having a base material composition (in weight-%) of: C 0.04-1.0; Mn 9.0-30.0; Al 0.05-15.0; Si 0.05-6.0; Cr?6.5; Cu?4; Ti+Zr?0.7; Nb+V?0.5, remainder iron including unavoidable steel-incidental elements, the steel strip undergoes annealing and subsequently is coated electrolytically with a coat formed from zinc or a zinc-containing alloy. During the course of annealing of the steel strip at temperatures between 800 and 1000° C. under a N2-H2 containing atmosphere, a surface-near zone is formed which is enriched with nitrides through reaction with elements contained in the steel, thereby preventing molten zinc from penetrating into the base material during welding of the coated steel strip.

Abstract: One aspect of the invention is a method of surface alloying stainless steel, In one embodiment, the method includes providing a stainless steel surface having an initial amount of iron and an initial amount of chromium; and preferentially removing iron from the stainless steel surface to obtain a surface having an amount of iron less than the initial amount of iron and an amount of chromium greater than the initial amount of chromium. Another aspect of the invention is a unitary stainless steel article.

Abstract: A steel which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or more of Cr: 0.05 to 1.5%, V: 0.05 to 0.2%, Mo: 0.05 to 0.4%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel being formed with (a) a nitrided layer having a certain thickness range and a nitrogen concentration higher than the nitrogen concentration of the steel by 0.02 mass % or more and (b) a low carbon region having a certain depth range from the surface of the steel and having a carbon concentration of 0.9 time or less the carbon concentration of the steel.

Abstract: A device has a magnetically shielded component that is magnetically shielded from an external magnetic field, and a housing. The housing is made from a ferritic stainless steel that has an austenitized surface layer rendered on the surface, and an internal layer portion having an internal ferrite phase that functions as a magnetic shield for the magnetically shielded component.

Abstract: Provided are a powder for a magnet, which provides a rare-earth magnet having excellent magnet properties and which has excellent formability, a method for producing the powder for a magnet, a powder compact, a rare-earth-iron-based alloy material, and a rare-earth-iron-nitrogen-based alloy material which are used as materials for the magnet, and methods for producing the powder compact and these alloy materials. Magnetic particles 1 constituting the powder for a magnet each have a texture in which grains of a phase 3 of a hydride of a rare-earth element are dispersed in a phase 2 of an iron-containing material, such as Fe. The uniform presence of the phase 2 of the iron-containing material in each magnetic particle 1 results in the powder having excellent formability, thereby providing a powder compact 4 having a high relative density.

Abstract: A nitriding process for a maraging steel is provided in order to increase the compressive residual stress of the maraging steel. A workpiece is made of maraging steel in which titanium is solid solved, and a partial amount of the titanium is oxidized at the surface of the workpiece so that titanium oxide is positively generated and concentrated at the surface. Then a reducing treatment is sufficiently performed as a pretreatment of a nitriding step, thereby removing oxygen. As a result, surface concentration of the titanium in an activated state is increased. Next, by performing the nitriding treatment, the reduced titanium and the solid solved titanium combine with nitrogen as titanium nitride. The titanium is in the activated state and is thereby easily nitrided. Moreover, the surface concentration of the titanium in the activated state is high, whereby a large amount of nitrogen infiltrates into the workpiece.

Abstract: The present invention comprises the nitrogen alloying of stainless steel with a gaseous nitrogen compound such as nitrogen gas (N2), or ammonia (NH3) at high temperature wherein the reaction pressure is lowered. A base powder with properties similar to those of a martensitic stainless steel is prepared from a molten metal with the subsequent incorporation of selective additives such as cobalt, chromium, boron, copper, vanadium, niobium and mixtures thereof to improve high temperature resistance to scuffing and adhesive wear. The molten mixture is then atomized by water- or air-atomization to yield a base powder which is mixed with nitrogen or ammonia gas at various pressures in a static or fluidized bed to provide a nitrogen alloyed particulate, i.e., a nitrided particulate alloy. The powder is heated in a hot isostatic press under vacuum with argon gas at reduced pressure and later cooled to ambient temperature.

Abstract: A method of activating an article of passive ferrous or non-ferrous metal by heating at least one compound containing nitrogen and carbon, wherein the article is treated with gaseous species derived from the compound. The activated article can be subsequently carburised, nitrided or nitrocarburised in shorter time at lower temperature and resulting superior mechanical properties compared with non-activated articles and even articles of stainless steel, nickel alloy, cobalt alloy or titanium based material can be carburised, nitrided or nitrocarburised.

Abstract: The invention relates to steel which is characterized by the following composition as expressed in percentages by weight: —C=0.18 0.30%, —Co=5-7%, —Cr=2-5%, —Al=1-2%, —Mo+W/2=1-4%, —V=trace 0.3%, —Nb=trace 0.1%, —B=trace—50 ppm, —Ni=10.5-15% with Ni?7+3.5 Al, —Si=trace 0.4%, —Mn=trace 0.4%, —Ca=trace—500 ppm, —Rare earths=trace—500 ppm, —Ti=trace—500 ppm, —O=Trace—200 ppm if the steel is obtained by means of powder metallurgy or trace—50 ppm if the steel is produced in air or under a vacuum from molten metal, —N=trace—100 ppm, —S=trace—50 ppm, —Cu=trace—1%, and —P=trace—200 ppm, the remainder including iron and the inevitable impurities resulting from production. The invention also relates to a method of producing a part from said steel and to the part thus obtained.

Abstract: A method for refining the texture of a ferrous material. The method includes a first step and a second step. The first step includes a step of making carbide particles in a portion of a base material smaller. The second step includes a step of nitriding at least a part of said portion.

Abstract: The invention relates to a method for producing a brake disc (BS) for a vehicle, comprising a main body (G) of a metal material, in particular gray cast iron, which has friction surfaces (R). The friction surfaces (R) are after-treated according to the invention by carboring, carbonitriding, case hardening, gas nitriding, oxide nitriding, gas nitro carburizing, plasma nitriding, plasma oxidizing, borating, plasma carborating or plasma borating.

Abstract: Disclosed are partially deactivated metal catalysts useful for modifying structures of nanomaterials. The present invention is also directed to a method for preparing the partially deactivated metal catalysts, which comprises patterning a substrate with micelles containing iron nanoparticles, removing the micelles from the patterned substrate to deposit the iron nanoparticles thereon, nitriding the iron nanoparticles using a nitrogen plasma, and exposing the nitrided iron nanoparticles to a mixture of ethanol and nitric acid to remove iron from the surface of the nitrided nanoparticles. The iron nitride metal catalyst with a nano-size according to the present invention comprises a core that includes deactivated iron nitride and an active shell surrounding the core. Thus, when preparing a carbon nanotube, the metal catalyst can be effectively used to control the number of walls formed in the carbon nanotube.

Abstract: A metal composite for use in electrochemical devices is disclosed. The metal composite comprises a stainless steel interior component and a deposited nitrided metal exterior layer, wherein the nitrided exterior layer has lower electric contact resistance and greater corrosion resistance than the stainless steel interior component. A bipolar plate made of such metal composite and methods of producing the metal composite and bipolar plate are also disclosed.

Abstract: A Ni-free stainless steel product excellent in workability and corrosion resistance and a method for manufacturing such stainless steel product. A ferritic stainless steel product containing 18 to 24% by mass of Cr and 0 to 4% by mass of Mo is brought into contact with an inert gas containing a nitrogen gas at 800 degrees C. or above to subject it to nitrogen absorption treatment so that the product is austenitized partially or wholly to obtain such nickel-free product.

Abstract: A highly corrosion-resistant member that is equipped with: a substrate made of stainless steel; an intermediate layer coated on at least a part of a surface of the substrate; and an amorphous carbon film coated on at least a part of a surface of the intermediate layer is completed by forming the intermediate layer and amorphous carbon film at such a low temperature that a temperature of the surface of the substrate is 450° C. or less. Another highly corrosion-resistant member that is equipped with: a substrate made of stainless steel, substrate whose superficial-layer portion is subjected to nitriding treatment; and an amorphous carbon film coated on at least a part of a surface of the superficial-layer portion is completed by carrying out the nitriding treatment and a formation of the amorphous carbon film at such a low temperature that a temperature of a surface of said substrate is 450° C. or less.

Abstract: A treated austenitic steel and method for treating same includes an austenitic steel and a non-metal chemical element incorporated into a surface of the steel. The surface has a bi-layered structure of a compound layer at a top and an underlying diffusion layer, which protects said surface against hydrogen embrittlement.