Abstract: A method for electrolytically passivating an outermost chromium or chromium alloy layer to increase corrosion resistance thereof, including steps of (i) providing a substrate comprising said outermost chromium or chromium alloy layer, (ii) providing or manufacturing an aqueous, acidic passivation solution comprising trivalent chromium ions, phosphate ions, one or more organic acid residue anion, (iii) contacting the substrate with the passivation solution and passing an electrical current between the substrate as a cathode and an anode in the passivation solution such that a passivation layer is deposited onto the outermost layer, wherein the trivalent chromium ions are obtained by chemically reducing hexavalent chromium in presence of phosphoric acid and at least one reducing agent, with the proviso that during or after the chemical reducing the one or more than one organic acid residue anion is present for the first time in the passivation solution.

Abstract: The metal alloy is a possible replacement for/alternative to cupronickel cladding material used on currently-circulating clad coins. In the preferred embodiment, the (steel) metal alloy cladding material comprises 73-77% iron, 22-26% nickel, 0.2-0.5% carbon, and 1-5% manganese. The cladding material has an International Annealed Copper Standard (IACS) conductivity of less than 2%, a permeability of approximately 1.0-1.1, and a hardness value of 50-70 HRC 15 T (Rockwell Hardness). In alternative embodiments, the steel alloy comprises a monolithic coin or a core that may be plated with other metals.

Abstract: A method of welding workpieces of high-temperature superalloys is provided. Welding filler is applied in a plurality of layers to a surface of the workpiece via a heat input zone and a supply zone for supplying the welding filler into the heat input zone. The heat input zone and the supply zone on the one hand and the workpiece surface on the other hand are moved in relation to one another. A polycrystalline weld seam is generated by remelting a previously applied layer of the plurality of layers. Welding parameters are chosen such that a cooling rate during a solidifying of the material is at least 8000 Kelvins per second. Further, a welding apparatus for carrying out such a method is provided.

Abstract: A method is provided that includes first etching a substrate according to a first mask. The first etching forms a first etch feature in the substrate to a first depth. The first etching also forms a sliver opening in the substrate. The sliver opening may then be filled with a fill material. A second mask may be formed by removing a portion of the first mask. The substrate exposed by the second mask may be etched with a second etch, in which the second etching is selective to the fill material. The second etching extends the first etch feature to a second depth that is greater than the first depth, and the second etch forms a second etch feature. The first etch feature and the second etch feature may then be filled with a conductive metal.

Abstract: The invention relates to a process for preparing a composition comprising 10 to 45% of the total solids weight lignin, polyacrylonitrile or a polyacrylonitrile copolymer, and a solvent to form a lignin-based polyacrylonitrile-containing dope and the resulting products. The dope can be processed to produce fibers, including precursor, oxidized and carbonized fibers. The oxidized fibers are of value for their flame resistant properties and carbonized fibers are suitable for use in applications requiring high strength fibers, or to be used to form composite materials.

Abstract: A protective coating system includes a nickel-aluminum-zirconium alloy coating having beta phase nickel-aluminum and at least one phase selected from gamma phase nickel and the gamma prime phase nickel-aluminum. The nickel-aluminum-zirconium alloy coating comprises 10 vol % to 60 vol % of the beta phase nickel-aluminum or 25 vol % to 75 vol % of the beta phase nickel-aluminum.

Abstract: A method of welding including forming a filler material of a first oxide dispersoid metal, the first oxide dispersoid material having first strengthening particles that compensate for decreases in weld strength of friction stir welded oxide dispersoid metals; positioning the filler material between a first metal structure and a second metal structure each being comprised of at least a second oxide dispersoid metal; and friction welding the filler material, the first metal structure and the second metal structure to provide a weld.

Abstract: A precursor for a Nb3Sn superconductor wire to be manufactured by the internal diffusion method, includes a plurality of Nb-based single core wires, each of which includes a Nb-based core coated with a Cu-based coating including a Cu-based matrix, a plurality of Sn-based single core wires, each of which includes a Sn-based core coated with a Cu-based coating including a Cu-based matrix; and a cylindrical diffusion barrier including Ta or Nb, in which the plurality of Nb-based single core wires and the plurality of Sn-based single core wires are regularly disposed, wherein the plurality of Nb-based single core wires include Nb-based single core wires having a Cu/Nb ratio of 0.4 or more, wherein the Cu/Nb ratio is a cross sectional area ratio of the Cu-based coating to the Nb-based core.

Abstract: Disclosed herein are a printed circuit board having a copper plated layer with an anchor shaped surface and roughness by forming the copper plated layer having an anisotropic crystalline orientation structure using a plating inhibitor at the time of forming the copper plated layer serving as a circuit wiring and using composite gas plasma and a dilute acid solution, and a method of manufacturing the same.

Abstract: The present invention relates to dispersion strengthened platinum-base alloys, and more particularly to a method for welding of these alloys and is based on the object of providing an improved process for connecting oxide-dispersed precious metal sheets and a device for carrying out this process.

Abstract: Polycrystalline diamond compacts for use in artificial joints achieve reduced corrosion and improved biocompatibility through the use of solvent metal formulations containing tin and through the control of solvent metal pore size, particularly in inner layers of the compact. Solvent metal formulations containing tin have been discovered which provide sintering ability, part strength, and grind resistance comparable to levels achieved by using CoCrMo solvent metals. It has been discovered that limiting the solvent metal pore size in the diamond layers minimizes or eliminates the occurrence of micro cracks in the solvent metal and significantly reduces the corrosion of the compact as manifested by the release of heavy metal ions from the compact. Polycrystalline diamond compacts which utilize both the solvent metal formulations containing tin and the control of pore sizes achieve significantly reduced corrosion and improved biocompatibility compared to prior art polycrystalline diamond compacts.

Abstract: A method of manufacturing a copper foil for a printed wiring board, characterized in that a roughened layer of roughening copper grains is formed on at least one surface of the copper foil by using an electrolytic bath of sulfuric acid and copper sulfate, and the electrolytic bath contains tungsten ions and/or arsenic ions and further contains an alkyl sulfate-based anionic surfactant. The object of the present invention is to provide a method of manufacturing a copper foil for a printed wiring board, wherein in particular a roughened layer on the copper foil can be improved to enhance the adhesive strength between the copper foil and a resin substrate without deteriorating other properties of the copper foil.

Abstract: A surface treatment method for aluminum or aluminum alloy includes the following steps: An aluminum or aluminum alloy substrate is provided. A metallic nickel layer is formed on the aluminum or aluminum alloy substrate by replacement reaction using a water solution. The water solution substantially comprises nickel sulfate, sodium citrate, potassium sodium tartrate, and sodium hydroxide. An electroless nickel layer is then formed on the metallic nickel layer by electroless nickel plating. An article manufactured by the method is also provided.

Abstract: The present disclosure relates to shims 10, 24 adapted for placement between a rocker shaft 42 and rocker shaft mounts 62, 64. The rocker shaft mounts 62, 64 project from the cylinder head 60 of an internal combustion engine. The shims 10, 24 are composed of a copper alloy, preferably bronze.

Abstract: A method of welding including forming a filler material of a first oxide dispersoid metal, the first oxide dispersoid material having first strengthening particles that compensate for decreases in weld strength of friction stir welded oxide dispersoid metals; positioning the filler material between a first metal structure and a second metal structure each being comprised of at least a second oxide dispersoid metal; and friction welding the filler material, the first metal structure and the second metal structure to provide a weld.

Abstract: Various embodiments provide a method for depositing metal on a substrate. The method may include carrying out a first immersion plating process, thereby forming a first metal portion on the substrate; providing an immersion plating activating substance on the first metal portion; and carrying out a second immersion plating process using the immersion plating activating substance, thereby forming a second metal portion on the first metal portion.

Abstract: A material for electric sliding contact comprising, on a conductive substrate, a first layer composed of a noble metal or an alloy comprising the noble metal as a major component with an arithmetic average roughness Ra of (A) ?m and, as an upper layer of the first layer, a second layer composed of a noble metal or an alloy comprising the noble metal as a major component with a covering thickness of from 0.001×(A) ?m or more to (A) ?m or less, wherein the noble metal forming the second layer or the noble metal as a major component of the alloy forming the second layer is a different element from the noble metal forming the first layer or the noble metal as a major component of the alloy forming the first layer.

Abstract: A new process and technical arrangement has been established for the production of grain free metal products, which can be extruded directly from the melt, by inserting a seed crystal from a seeding chamber into the opening of the extrusion jet of the melting vessel. The seed crystal will break by contact the surface tension of the liquid metal in the extrusion jet channel, which is slightly undercooled. Upon establishing contact, the temperature at the meeting point of the seed crystal and the liquid metal will be raised by RF-heating to permit the extrusion of the seed crystal backwards, ensuring that metal and seed crystal maintain contact and crystal growth will continue. It has been discovered, that single crystals with the orientation of the seed crystal will continue to grow and to establish high hardness. Speed of extrusion is exceeded to reach only grain free structure in the grown metal.

Abstract: A lead frame having a coating of organic compounds on its lead fingers prevents tin and flux from contaminating the lead fingers after die attach. The coating is removed prior to wire bonding. The coating allows for reliable second bonds (bond between wires and lead fingers) to be formed, decreasing the likelihood of non-stick and improving wire peel strength.

Abstract: A silver-coated composite material for movable contact includes a base material composed of an alloy whose main component is iron or nickel, an under layer which is formed at least on part of the surface of the base material and which is composed of any one of nickel, cobalt, nickel alloy and cobalt alloy, an intermediate layer which is formed on the under layer and which is composed of copper or copper alloy and an outermost layer which is formed on the intermediate layer and which is composed of silver or silver alloy, and wherein a total thickness of the under layer and the intermediate layer falls within a range more than 0.025 ?m and less than 0.20 ?m.

Abstract: One aspect is a device including at least two interconnected metal parts. The two interconnected parts are formed from metals with different melting temperature from the group consisting of the elements Pt, Pd, Ag, Au, Nb, Ta, Ti, Zr, W, V, Hf, Mo, Co, Cr, Ni, Ir, Re, Ru as well as alloys on the basis of at least one of those elements. The metal part with the lower melting temperature is fused onto the metal part with the higher melting temperature and both parts are friction-locked and/or form-locked with each other.

Abstract: A Ni plating is applied on a base metal in a metal strip form, and a brightener-free Sn-(1 to 4% by mass)Cu plating is applied on the Ni plating. The metal strip is heat-treated at a temperature at or above the melting point (solidus line) of a Sn-(1 to 4% by mass)Cu alloy to form a Cu—Sn compound layer or a Cu—Ni—Sn-compound layer on the Ni plating layer and a Sn layer or a Sn—Cu-ally layer on the Cu—Sn compound layer or the Cu—Ni—Sn-compound layer. The metal strip is further fabricated into a connector. Thus, a metal strip, which has good soldability on a substrate, is free from the occurrence of whiskers at a terminal part during storage or upon fitting into FPC or FFC, and is necessary for a lead-free connector, can be realized.

Abstract: Methods of producing one or more biaxially textured layer on a substrate, and articles produced by the methods, are disclosed. An exemplary method may comprise electrodepositing on the substrate a precursor material selected from the group consisting of rare earths, transition metals, actinide, lanthanides, and oxides thereof. An exemplary article (150) may comprise a biaxially textured base material (130), and at least one biaxially textured layer (110) selected from the group consisting of rare earths, transition metals, actinides, lanthanides, and oxides thereof. The at least one biaxially textured layer (110) is formed by electrodeposition on the biaxially textured base material (130).

Abstract: To form high performance bonding connections suitable for producing micro-structured components made of a plurality of individual layers, bonding by the steps; providing at least two work pieces; forming a metal bonding layer on at least one side of at least one of said at least two work pieces by chemical or electrolytic metal plating method; the metal bonding layer being a nickel/phosphorous alloy having a prescribed phosphorous content and prescribed thickness; forming a bonding arrangement comprising said work pieces so that there is at least one metal bonding layer between said at least two respective work pieces; heating at a prescribed heating rate to a temperature above the melting temperature of the bonding layer; bonding the two work pieces by applying contact pressure within a prescribed range; and cooling at a prescribed rate.

Abstract: Problems to be solved by the invention: It is an object of the present invention to provide a brass-plated steel wire for reinforcing rubber articles capable of surely improving adhesiveness between brass-plated steel wire and rubber and a method for manufacturing the same. Means for solving the problem: A brass-plated steel wire 10 for reinforcing rubber articles according to the invention comprises a steel wire having a brass-plating layer 11 thereon, wherein the brass-plating layer 11 has an amorphous portion 11a formed of crystal grains having a grain size of 20 nm or less. It may also be such that the brass-plating layer 11 is of a laminated structure 13 of an amorphous portion 11a on the surface side and a crystalline portion 11b on the inner side, wherein the amorphous portion 11a is formed of crystal grains having a grain size of 20 nm or less and the crystalline portion 11b is formed of crystal grains having a grain size of more than 20 nm.

Abstract: A material for electric contact comprising, on a conductive substrate, a first layer composed of a noble metal or an alloy comprising the noble metal as a major component with an arithmetic average roughness Ra of (A) ?m and, as an upper layer of the first layer, a second layer composed of a noble metal or an alloy comprising the noble metal as a major component with a covering thickness of from 0.001×(A) ?m or more to (A) ?m or less, and wherein the noble metal forming the second layer or the noble metal as a major component of the alloy forming the second layer is a different element from the noble metal forming the first layer or the noble metal as a major component of the alloy forming the first layer.

Abstract: A protective coating system includes a nickel-aluminum-zirconium alloy coating having at least one phase selected from gamma phase nickel, gamma prime phase nickel-aluminum, or beta phase nickel-aluminum in combination with the gamma phase nickel or the gamma prime phase nickel-aluminum. For example, the nickel-aluminum-zirconium alloy coating includes about 0.001 wt % to 0.2 wt % zirconium.

Abstract: A transparent substrate, especially made of glass, provided with a thin-film multilayer (20) that includes three silver layers (Ag1, Ag2, Ag3) and comprises, alternately on the substrate, a titanium dioxide layer (21), a metal oxide layer (22), one of the silver layers (Ag1, Ag2, Ag3) and a covering layer (23), characterized in that: the metal oxide is zinc oxide; the covering layer (23) is a sacrificial metal; and an antireflection layer (24) comprising at least one metal oxide is deposited on the covering layer (23) for the silver layer (Ag3) furthest away from the substrate.

Abstract: A structure and a method of forming the structure in high temperature sections of next generation nuclear and solar power plants where the structure consists of piping, ducting and enclosures fabricated from oxide dispersion strengthened (ODS) alloys joined by friction stir welding (FSW) to other ODS alloys or any alloy.

Abstract: A cast component having localized areas of improved physical properties is disclosed. The component may initially be produced having a void portion in a predetermined area requiring improved physical properties. A second molten material may be added to the void portion such that it chemically bonds to the void portion. The component may then be finished such to a final shape with a localized area of improved physical properties.

Abstract: A coating and coating process for incorporating surface features on an air-cooled substrate surface of a component for the purpose of promoting heat transfer from the component. The coating process generally comprises depositing a first metallic coating material on the surface of the component using a first set of coating conditions to form a first environmental coating layer, and then depositing a second metallic coating material using a second set of coating conditions that differ from the first set, such that an outer environmental coating layer is formed having raised surface features that cause the surface of the outer environmental coating layer to be rougher than the surface of the first environmental coating layer.

Abstract: There is provided a method for depositing a modified MCrAlY coating on a turbine blade tip. The method utilizes laser deposition techniques to provide a metallurgical bond between a turbine blade substrate, such as a superalloy substrate, and the modified MCrAlY composition. Further the modified MCrAlY coating has sufficient thickness such that a post-welding grinding operation to size the turbine blade to a desired dimension will not remove the modified MCrAlY coating entirely. The modified MCrAlY coating thus remains on the finished turbine blade tip after grinding.

Abstract: A coating which improves the wear performance of a part is described. The coating is applied over an article such as a part or a workpiece using an electroplating process. The coating broadly includes a cobalt material matrix with a hardness of at least 550 HV and a plurality of carbide particles distributed throughout the cobalt material matrix. The cobalt material matrix may be a cobalt-phosphorous alloy. The particles interspersed throughout the matrix may be chrome carbide or silicon carbide particles.

Abstract: A method for forming a plating film, comprising the steps of: applying a plating film onto an object to be plated at a first current density for a predetermined period in a plating bath having a cathode capable of varying current and an anode and; and maintaining the object to be plated at a second current density lower than the first current density. According to the present invention, it is possible to improve solderability of a plating film for conventional lead-free solder by a simple method, which allows the productivity to further enhanced, resulting in a plating film with reduced production costs.

Abstract: High density longitudinal magnetic recording media are formed with two magnetic layers for enhanced SMNR, high signal, low PW 50 and high resolution. The bilayer magnetic structure comprises a first magnetic layer optimized for SMNR and a second magnetic layer formed directly on the first magnetic layer and optimized for Ms. Embodiments of the present invention include first and second magnetic layers containing Co, Cr and Pt, wherein the first magnetic layer has a higher Cr content than the second magnetic layer and the second magnetic layer has a higher Co content than the first magnetic layer.

Abstract: The aim of the invention is to provide a metal strip for epitaxial coating with a biaxially textured layer, this metal strip, however, being able to be produced in an uncomplicated manner and having a high tensile strength, low magnetic losses and/or a high electrical conductivity. According to the invention, the metal strip is comprised of Nj, Cu, Ag or alloys thereof all serving as basic material, whereby the one-layer metal strip and, in the instance of a multilayer metal strip, at least one of its layers contains 10 nm to 5 ?m large, strength-increasing dispersoids comprised of carbides, borides, oxides and/or nitrides with a volume proportion ranging from 0.1 to 5%. In the instance of a multilayer metal strip, the layers form a composite, and at least one of the layers does not contain any dispersoids and has a biaxial texture. For the production, a starting material is used, which is comprised of Ni, Cu, Ag or of alloys thereof all serving as basic material and which contains 0.

Abstract: This invention provides a metal foil and an etching process which overcomes the problem of etching of the copper foil layer and the plating copper layer formed on a metal clad laminate during the conventional semi-additive process for producing printed wire boards. In the present invention, the metal foil and the metal foil with carrier foil include a nickel or tin layer 0.5 to 3 ?m thick formed on the external surface of a metal clad laminate which protects the surface of the plated layer during the final flash etching of the copper foil layer.

Abstract: A magnetic recording medium includes a substrate, an underlayer, a lower magnetic layer formed on the underlayer, an intermediate layer, and an upper magnetic layer formed on the intermediate layer. The intermediate layer is typically Ru, and promotes antiferromagnetic coupling between the upper and lower magnetic layers. The upper and lower magnetic layers are typically Co alloys. The lower magnetic layer has a high saturation magnetization Ms to promote high exchange coupling between the upper and lower magnetic layers. The dynamic coercivity of the lower magnetic layer is lower than the exchange field to ensure rapid switching of the lower magnetic layer.

Abstract: A spin-valve sensor with pinning layers comprising multiple antiferromagnetic films is disclosed. The multiple antiferromagnetic films are preferably selected from the same Mn-based (Ni—Mn or Pt—Mn) alloy system. The Mn content of the antiferromagnetic film in contact with the reference layer of the spin-valve sensor is selected in order to maximize its exchange coupling to the reference layer, thereby providing a high unidirectional anisotropy field for proper sensor operation. The Mn content of the other antiferromagnetic films not in contact with the reference layer of the spin-valve sensor is reduced in order to maximize the thermal stability and corrosion resistance of the spin-valve sensor for robust sensor operation at high temperatures in disk drive environments.

Abstract: A magnetic sensing element includes a laminate, the laminate including a first antiferromagnetic layer; a pinned magnetic layer, the magnetization direction thereof being pinned by the first antiferromagnetic layer; a nonmagnetic conductive layer; a free magnetic layer, the magnetization direction thereof being variable in response to an external magnetic field; a nonmagnetic interlayer; a ferromagnetic layer; and a second antiferromagnetic layer. The laminate has a recess extending through the second antiferromagnetic layer and the ferromagnetic layer, a bottom face of the recess lying in the nonmagnetic interlayer, the width of the bottom face in a track width direction being equal to a track width. The free magnetic layer is magnetized in a direction substantially orthogonal to the magnetization direction of the pinned magnetic layer as a result of magnetic coupling with the ferromagnetic layer. A method for making such a magnetic sensing element is also disclosed.

Abstract: A thermal spring magnetic medium is provided having first and second stacks providing two exchange coupled ferromagnetic layers having different Curie temperatures. The first stack has a high magneto-crystalline anisotropy, a relatively low saturation magnetization and a low Curie temperature. The second stack has a relatively low magneto-crystalline anisotropy, a high saturation magnetization and a high Curie temperature. Preferably the first stack includes an alloy of Fe—Pt or Co—Pt, and the second stack includes an allow of Co—Pt or Co—Pd. A disk drive system having the novel medium is also provided.

Abstract: A ferromagnetic thin-film based magnetic field sensor having a nonmagnetic intermediate layer with two major surfaces on opposite sides thereof upon one of which a magnetization reference layer is provided and upon the other there being provided a sensing layer. A spacer layer is provided on the sensing film to separate this sensing film from an augmenting film with the spacer layer being sufficiently thick so as to significantly reduce or eliminate topological coupling between the sensing and augmenting films, and to significantly randomize spin states of emerging electrons traversing therethrough.

Abstract: A magnetic sensing element includes a lower multilayer film including a lower pinned magnetic layer, a lower nonmagnetic layer, a free magnetic layer, an upper nonmagnetic layer, and an upper pinned magnetic layer; and an upper multilayer film including a lower pinned magnetic layer, a lower nonmagnetic layer, a free magnetic layer, an upper nonmagnetic layer, and an upper pinned magnetic layer. Each pinned magnetic layer includes a first pinned magnetic sublayer, a second pinned magnetic sublayer, and an intermediate nonmagnetic sublayer. By setting the magnetization direction of the second pinned magnetic sublayers in the lower multilayer film antiparallel to the second pinned magnetic sublayers in the upper multilayer film, the magnetic sensing element can output a pulsed signal directly when moving over a magnetization transition region.

Abstract: The subject of the invention is a layer system for the decorative coating of galvanizable work pieces. In order to have a layer system which meets strict requirements with regard to corrosion resistance and which, at the same time, has a high abrasion resistance and, in addition, provides a high degree of freedom with regard to decorative coloration, the invention proposes a layer system which is formed by galvanic deposition and comprises a base coat consisting of at least one bright layer and one discontinuous chrome layer as well as a cover coat of mechanically resistant materials deposited by the PVD process.

Abstract: A high areal recording density longitudinal magnetic recording medium having improved thermal stability and signal-to-medium noise ratio (“SMNR”), comprises: (a) a non-magnetic substrate having at least one surface; and (b) a layer stack overlying the at least one surface, comprising a plurality of vertically spaced-apart ferromagnetic layers, each vertically adjacent pair of ferromagnetic layers being spaced-apart by a respective non-magnetic spacer layer, wherein: (i) at least one of the plurality of vertically adjacent, spaced-apart pairs of ferromagnetic layers forms an anti-ferromagnetically coupled media (“AFC”) component of the magnetic recording medium; and (ii) at least one of the plurality of vertically adjacent, spaced-apart pairs of ferromagnetic layers forms a laminated media (“LM”) component of the magnetic recording medium.

Abstract: Laminated magnetic recording medium with two Co-containing layers separated by a non-magnetic Ru-containing interlayer is stabilized by Ru-containing layer between the recording layers and Co-containing stabilization layers through anti-ferromagnetic coupling. The insertion of Co layer beneath Ru spacer has resulted in increased coupling, and further coupling enhancement is achieved by low pressure process of Co and Ru layers.

Abstract: A magnetic recording medium such as a magnetic disk includes a NiP or ceramic glass substrate on which a seedlayer is sputtered in a low pressure inert gas atmosphere, the seedlayer comprising a ternary or quaternary alloy formed from a B2 lattice type alloy such as NiAl, CoTi, CoAl, NiTi, FeTi, CoFe, CoHf, CuZn, CoZr, and MnAl. For quaternary alloys in which elements X and Y are added to the B2 type alloy, X can be chosen from one or more elements selected from the group consisting of Co, Ni, Fe, Cu, V, Mn, and Zn, and Y can be chosen from one or more elements selected from the group consisting of Al, Nb, Ta, Hf, Zr, Zn, Ag, Au, Pt and Pd. The resulting seedlayer preferably has an A2 lattice structure.

Abstract: An anti-ferromagnetically coupled (“AFC”), high areal density magnetic recording medium of simplified thin film layer structure and having improved thermal stability and signal-to-medium noise ratio (“SMNR”) comprises a stack of thin film layers including, in overlying sequence from a surface of a non-magnetic substrate: (a) a non-magnetic seed layer (“SDL”); (b) at least one non-magnetic underlayer (“UL”); (c) a first ferromagnetic layer (“M1”); (d) a non-magnetic spacer layer (“SPL”); and (e) a second ferromagnetic layer serving as a magnetic recording layer (“M2”); wherein: the first ferromagnetic layer (c) serves as a combined interlayer (“IL”) and “bottom” magnetic layer (“BML”) and the non-magnetic spacer layer (d) provides RKKY-type coupling between the first ferromagnetic layer (c) and the second ferromagnetic layer (e) for stabilizing the medium via anti-ferromagnetic coupling

Abstract: A perpendicular magnetic recording medium, which has a low level of recording noise and sufficiently large perpendicular magnetic anisotropy energy relative to demagnetizing field energy, includes a substrate and a multi-layered magnetic film. The multi-layered magnetic film is composed of ferromagnetic metal layers of Co alloy containing at least Cr and non-magnetic metal layers of Pd alloy, each one layer of which are laminated alternately on top of one layer of the other. The ferromagnetic metal layers and the non-magnetic metal layers have a thickness of d1 and d2, respectively, with the ratio of d1/d2 being in the range of 1.5 to 4.0. This specific layer structure reduces the magnetic exchange interaction between magnetic particles in the multi-layered magnetic film. Therefore, the perpendicular magnetic recording medium is stable against thermal disturbance and has a low level of recording noise.

Abstract: A high areal recording density, anti-ferromagnetically coupled (“AFC”) perpendicular magnetic recording medium comprises: a layer stack formed over the surface of a non-magnetic substrate (2), comprising, in overlying sequence: an underlayer (3) comprised of a magnetically soft ferromagnetic material; at least one non-magnetic interlayer (4); a perpendicularly anisotropic stabilization layer (6) comprised of a hard ferromagnetic material; a non-magnetic spacer layer (7); and a perpendicularly anisotropic main recording layer (5) comprised of a hard ferromagnetic material; wherein the perpendicularly anisotropic stabilization layer (6) and the perpendicularly anisotropic main recording layer (5) are anti-ferromagnetically coupled (AFC) across the non-magnetic spacer layer (7) to orient the magnetic moments thereof anti-parallel and thereby provide the medium with increased