Abstract: A coating material has a first layer deposited on a base material and a second layer deposited on the first layer. The first layer is made of a Ni-base alloy or a Co-base alloy containing carbon as an unavoidable impurity. The second layer is made of a hard material containing carbide and a metal component. The first layer serves as a barrier for preventing carbon from being diffused from the second layer into the base material to prevent the base material from being carburized.

Abstract: Disclosed is an alloy coating which can be advantageously applied to members for high temperature apparatuses so as to prolong the service life of the members. The alloy coating comprises an alloy. This alloy comprises: at least one member, as a base, selected from the group consisting of Re, Ir, Nb, Ta, Mo, and W; and at least one alloying element for imparting corrosion resistance. A method for forming the alloy coating, and a member for high temperature apparatuses, to which the alloy coating has been applied, are also disclosed.

Abstract: Disclosed is an alloy coating which can be advantageously applied to members for high temperature apparatuses so as to prolong the service life of the members. The alloy coating comprises an alloy. This alloy comprises: at least one member, as a base, selected from the group consisting of Re, Ir, Nb, Ta, Mo, and W; and at least one alloying element for imparting corrosion resistance. A method for forming the alloy coating, and a member for high temperature apparatuses, to which the alloy coating has been applied, are also disclosed.

Abstract: Disclosed is an alloy coating which can be advantageously applied to members for high temperature apparatuses so as to prolong the service life of the members. The alloy coating comprises an alloy. This alloy comprises: at least one member, as a base, selected from the group consisting of Re, Ir, Nb, Ta, Mo, and W; and at least one alloying element for imparting corrosion resistance. A method for forming the alloy coating, and a member for high temperature apparatuses, to which the alloy coating has been applied, are also disclosed.

Abstract: This invention relates to a hard coating developed for applications involving high-temperature corrosion by improving the performance of TiN coatings while retaining the superior wear resistance and low friction coeffident of TiN itself. The nitride-based sliding material has a face-centered cubic crystalline structure with lattice constant of between 0.414 and 0.423 nm, and is made of mostly TiN but contains at least one element selected from the group containing Al, Cr, Zr and Hf; or comprises a nitride-based material containing substantially titanium nitride and at least one element selected from a group consisting of B and Si, and having a face-centered cubic crystalline structure comprising crystallites of an average size of not more than 9 nm.

Abstract: A coating material has a first layer deposited on a base material and a second layer deposited on the first layer. The first layer is made of a Ni-base alloy or a Co-base alloy containing carbon as an unavoidable impurity. The second layer is made of a hard material containing carbide and a metal component. The first layer serves as a barrier for preventing carbon from being diffused from the second layer into the base material to prevent the base material from being carburized.

Abstract: A manufacturing method, particularly a forging treatment and a heat treatment method of a Ni-based alloy having sulfidation-corrosion resistance used for component members of corrosion-resistant high-temperature equipment, that is, Waspaloy (a trademark of United Technologies) or its improved Ni-based alloy wherein the high temperature sulfidation-corrosion resistance of the alloy can be improved while maintaining hot strength properties is disclosed. A Ni-based alloy used for the method consists essentially of 0.005 to 0.1% C, 18 to 21% Cr, 12 to 15% Co, 3.5 to 5.0% Mo, not more than 3.25% Ti and 1.2 to 4.0% Al (expressed in mass percentage), with the balance substantially comprising Ni.

Abstract: The invention aims to provide a hard film which is improved in high-temperature corrosion resistance without impairing high sliding characteristics (wear resistance, low frictional coefficient) inherent in a titanium nitride thin film and which is suitable for a slide member such as a bearing or a seal used in rotary machines operated at a high temperature, such as a steam turbine and a gas turbine. For attaining this aim, the invention provides a Cr-containing titanium nitride film which is composed of a nitride containing Ti and Cr as main components, the crystal particles thereof having a face-centered cubic crystal structure, and the crystal thereof being highly oriented toward (200) face.

Abstract: A plating analysis method is disclosed for electroplating in a system in which resistance of an anode and/or a cathode cannot be neglected. This method comprises giving a three-dimensional Laplace's equation, as a dominant equation, to a region containing a plating solution; discretizing the Laplace's equation by the boundary element method; giving a two-dimensional or three-dimensional Poisson's equation dealing with a flat surface or a curved surface, as a dominant equation, to a region within the anode and/or the cathode; discretizing the Poisson's equation by the boundary element method or the finite element method; and formulating a simultaneous equation of the discretized equations to calculate a current density distribution i and a potential distribution &phgr; in the system. The method can obtain the current density and potential distributions efficiently for a plating problem requiring consideration for the resistance of an electrode.

Abstract: A manufacturing method, particularly a heat treatment method of a Ni-based alloy having sulfidation-corrosion resistance used for component members of corrosion-resistant high-temperature equipment, that is, Waspaloy (a trademark of United Technologies) or its improved Ni-based alloy wherein the high temperature sulfidation-corrosion resistance of the alloy can be improved while maintaining hot strength properties is disclosed. A Ni-based alloy used for the method consists essentially of 0.005 to 0.1% C, 18 to 21% Cr, 12 to 15% Co, 3.5 to 5.0% Mo, not more than 3.25% Ti and 1.2 to 4.0% Al (expressed in mass percentage), with the balance substantially comprising Ni. In the manufacturing method of a Ni-based alloy having improved sulfidation-corrosion resistance, the alloy is, after solution heat treatment, subjected to stabilizing treatment at a temperature not lower than 860° C. and not higher than 920° C. for 1 to 16 hours, and aging treatment at a temperature not lower than 680° C.

Abstract: A manufacturing method, particularly a forging treatment and a heat treatment method of a Ni-based alloy having sulfidation-corrosion resistance used for component members of corrosion-resistant high-temperature equipment, that is, Waspaloy (a trademark of United Technologies) or its improved Ni-based alloy wherein the high temperature sulfidation-corrosion resistance of the alloy can be improved while maintaining hot strength properties is disclosed. A Ni-based alloy used for the method consists essentially of 0.005 to 0.1% C, 18 to 21% Cr, 12 to 15% Co, 3.5 to 5.0% Mo, not more than 3.25% Ti and 1.2 to 4.0% Al (expressed in mass percentage), with the balance substantially comprising Ni.

Abstract: The invention aims to provide a hard film which is improved in high-temperature corrosion resistance without impairing high sliding characteristics (wear resistance, low frictional coefficient) inherent in a titanium nitride thin film and which is suitable for a slide member such as a bearing or a seal used in rotary machines operated at a high temperature, such as a steam turbine and a gas turbine. For attaining this aim, the invention provides a Cr-containing titanium nitride film which is composed of a nitride containing Ti and Cr as main components, the crystal particles thereof having a face-centered cubic crystal structure, and the crystal thereof being highly oriented toward (200) face.

Abstract: A manufacturing method, particularly a heat treatment method of a Ni-based alloy having sulfidation-corrosion resistance used for component members of corrosion-resistant high-temperature equipment, that is, Waspaloy (a trademark of United Technologies) or its improved Ni-based alloy wherein the high temperature sulfidation-corrosion resistance of the alloy can be improved while maintaining hot strength properties is disclosed. A Ni-based alloy used for the method consists essentially of 0.005 to 0.1% C, 18 to 21% Cr, 12 to 15% Co, 3.5 to 5.0% Mo, not more than 3.25% Ti and 1.2 to 4.0% Al (expressed in mass percentage), with the balance substantially comprising Ni. In the manufacturing method of a Ni-based alloy having improved sulfidation-corrosion resistance, the alloy is, after solution heat treatment, subjected to stabilizing treatment at a temperature not lower than 860° C. and not higher than 920° C. for 1 to 16 hours, and aging treatment at a temperature not lower than 680° C.

Abstract: Disclosed is an alloy coating which can be advantageously applied to members for high temperature apparatuses so as to prolong the service life of the members. The alloy coating comprises an alloy. This alloy comprises: at least one member, as a base, selected from the group consisting of Re, Ir, Nb, Ta, Mo, and W; and at least one alloying element for imparting corrosion resistance. A method for forming the alloy coating, and a member for high temperature apparatuses, to which the alloy coating has been applied, are also disclosed.

Abstract: An object to be analyzed for corrosion and corrosion prevention is divided into a plurality of adjacent regions of plural types by a dividing plane, with one of the adjacent regions being referred to as an attentional region with a boundary as the dividing plane and the other as a non-attentional region with a boundary as the dividing plane. An initial current density or an initial potential is imparted to each element of the boundary of the non-attentional region to effect a boundary element analysis for determining a relationship between a potential and a current density in each the element. A potential distribution and a current density distribution in the attentional region in its entirety are determined, using the relationship between the potential and the current density in each the element of the boundary of the non-attentional region as a boundary condition for the attentional region.

Abstract: An object of the present invention is to provide a method for forming an initial anticorrosive film in an absorption chiller-heater, by selecting optimal conditions of absorbent solution, steel material surface and film-forming operation for forming a good initial anticorrosive film. In the process for forming an initial anticorrosion film in an absorption chiller-heater having steel parts and containing an absorbent solution comprising lithium bromide as its main component and containing a lithium molybdate corrosion inhibitor according to the present invention, the main characteristics are that at least part of the steel parts of the absorption chiller-heater contacting with an absorbent solution at a temperature of higher than 100.degree. C. include a bare metal surface having an arithmetic mean surface roughness of not more than 1.0 .mu.

Abstract: A high-temperature sulfidation-corrosion resistant nickel-base alloy includes 12.about.15 weight % of cobalt, 18.about.21 weight % of chromium, 3.5.about.5 weight % of molybdenum, 0.02.about.0.1 weight % of carbon, at most 2.75 weight % of titanium, and at least 1.6 weight % of aluminum. The remainder is essentially of nickel except for impurities. The high-temperature sulfidation-corrosion resistant nickel-base alloy has sufficient high-temperature strength and is highly resistant to a high-temperature sulfidation corrosion.

Abstract: Austenitic cast iron has excellent corrosion resisting properties and has been preferentially used in machines or machine parts intended for handling corrosive fluids such as seawater. Cases, however, have been reported of machines or machine parts made of austenitic cast iron failing after they had been put to prolonged service at relatively low temperatures. The present inventors have located stress corrosion cracking at the cause of this failure.In accordance with the present invention, methods of using salt water resisting machines or machine parts made of austenitic cast iron that has graphite in the form of spheroids or nodules and which comprises by weight %: C.ltoreq.3.0, Si=1.0-3.0, Mn.ltoreq.1.5, P.ltoreq.0.08, Ni>24-28%, Cr.ltoreq.5.5 and the balance being Fe to minimize stress corrosion are provided.