Japan Science and Technology Agency

Ebara Corporation

Sapporo Electroplating Industrial Co., Ltd.

Other

Hokkaido University

Hitachi Construction Machinery Co., Ltd.

Agency of Industrial Science and Technology

Dbc System Co., Ltd.

Mitsubishi Hitachi Power Systems, Ltd.

Mitsubishi Power, Ltd.

Narita, Toshio

Toshio Narita

Isao Ishikawa

Takeshi Izumi

Hiroshi Yakuwa

Shigenari Hayashi

Matsuho Miyasaka

Michiaki Souma

Manabu Noguchi

Tadashi Kasuya

Takayuki Yoshioka

Shuhei Nakahama

Yoshitaka Kojima

Masamichi Kawasaki

Daisuke Yoshida

Tatuo Ishikawa

Takumi Nishimoto

Michihisa Fukumoto

Akira Mebata

Hideyuki Arikawa

In an alloy coating film having a diffusion barrier layer and an aluminum reservoir layer on a substrate, the diffusion barrier layer is composed of a single phase that is a Re&#x2014;Cr&#x2014;Ni&#x2014;Al system &#x3c3; phase containing Al by less than 1 atomic %, or composed of a first phase which is the Re&#x2014;Cr&#x2014;Ni&#x2014;Al system &#x3c3; phase and one or more second phases selected from a &#x3b3; phase, &#x3b3;' phase and &#x3b2; phase.

Alloy coating film, method for production of alloy coating film, and heat-resistant metal member

Disclosed is a multilayer alloy coating film capable of maintaining heat resistance, high-temperature oxidation resistance and creep resistance for a long time even in an ultra high temperature environment. The multilayer alloy coating film comprises a barrier layer formed on a base surface, and an aluminum reservoir layer formed on the barrier layer and composed of an alloy containing Al. The barrier layer comprises an inner sacrificial barrier layer composed of an alloy containing Re, an inner stabilization layer formed on the inner sacrificial barrier layer, a diffusion barrier layer formed on the inner stabilization layer and composed of an alloy containing Re, an outer stabilization layer formed on the diffusion barrier layer, and an outer sacrificial barrier layer formed on the outer stabilization layer and composed of an alloy containing Re.

Multilayer alloy coating film, heat-resistant metal member having the same, and method for producing multilayer alloy coating film

A diffusion barrier alloy film has a diffusion barrier layer which has more excellent diffusion barrier properties than an Re&#x2014;Cr alloy film, and can stand usage at higher temperatures (e.g., 1150&#xb0; C. or higher). The diffusion barrier layer is made of an Re&#x2014;W alloy &#x3c3; phase containing 12.5 to 56.5% of W in terms of atomic composition and the remainder of Re excluding unavoidable impurities. A metal base has a surface coated with a diffusion barrier layer. If required, the diffusion barrier layer has a surface coated with a diffusion alloy layer containing 10% or greater and less than 50% of Al, Cr, or Si in terms of atomic composition, providing a high-temperature apparatus member.

Diffusion barrier alloy film and high-temperature apparatus member

Disclosed is a method of forming a high-temperature corrosion-resistant film, which comprises placing a container containing a film-forming fine powder and a target member capable of being heated by an electric current heating process, in an atmosphere-controllable treatment chamber, and floating the fine powder and subjecting the target member to the electric current heating process to allow vapor of the fine powder generated by the heating to be diffused into the target member from a surface thereof so as to form a diffusion film layer, and allow the floated fine powder to be attached onto the surface so as to form a fine-powder film layer on the diffusion film layer. The target member may be masked to form the film only in a non-masked region of the target member. Alternatively, a specific region of the target member may be cooled at a temperature precluding the film formation to prevent the film from being formed in the specific region. The method of the present invention makes it possible to form a high-temperature corrosion-resistant film having an 'intended configuration' in a 'desired region' of a heat-resistant material at &#x201c;low cost&#x201d; with &#x201c;high productivity&#x201d;.

Method of forming high temperature corrosion resistant film

Disclosed is a method for forming a high-Re-content alloy film, such as a Re-based film containing Re at 98% or more by atomic composition, or an alloy film containing Re in the range of 65 to less than 98% by atomic composition and at least one of Ni, Fe and Co. The method comprises performing an electroplating process using an electroplating bath containing an aqueous solution which includes a perrhenate ion, at least one ion selected from the group consisting of Ni, Fe, Co and Cr ions, and at least one of a Li ion and a Na ion. The present invention allows a high-Re-content alloy film usable as a corrosion-resistant alloy coating for a high-temperature component or the like to be formed through an electroplating process using an aqueous solution, so as to provide heat/corrosion resistances to the component, even if it has a complicated shape, in a simplified manner at a low cost.

Method for forming Re alloy coating film having high-Re-content through electroplating

A composite resistive to high-temperature corrosion and abnormal oxidization, maintains original excellent high-temperature characteristics of Ni alloys over a long period of time, and suitable for applications in a high-temperature such as gas turbines, jet engines, and elements for exhaust-gas systems. A heat-resistant Ni-alloy composite has excellent high-temperature oxidation resistance, including a Ni-alloy substrate that has been subjected to an Al-diffusing treatment. The surface coat has a multi-layer structure including an inner layer composed of an &#x3b1;-Cr phase and an outer layer composed of a &#x3b2; phase (Ni&#x2014;Al&#x2014;Cr) and a &#x3b3;' phase (NiAl(Cr)) on the substrate surface. The Al content in the outer layer is at least 20 atomic percent. The &#x3b1;-Cr phase functions as a diffusion-barrier layer. The outer layer retains and secures a high Al content required for self-regeneration of a defective portion of the AlOlayer damaged in an operating condition.

Heat-resistant nickel-alloy composite excellent in high-temperature oxidation resistance

Disclosed is a Re alloy coating for diffusion barrier, such as a high-temperature equipment member, which comprises an atomic composition of 30% to less than 90% Re; and an atomic composition of 5% to less than 60% X (wherein X is at least one selected from the group consisting of Cr, Mo and W), with the remainder except for inevitable impurities being at least one selected from the group consisting of Ni, Fe and Co. Even if the alloy coating for diffusion barrier includes a diffusion layer containing at least one of the group consisting of Al, Si and Cr, a desired alloy composition of the alloy coating for diffusion barrier can be assured by a surface coating process and diffused components from the substrate while substantially preventing the diffusion of the elements of the diffusion layer during a homogenizing heat treatment. The alloy coating for diffusion barrier may include a Re-containing-alloy stress relief layer inserted between the film and the substrate. The Re alloy coating can suppress the deterioration of the substrate and the coating layer due to the reaction therebetween to provide an extended life span of the equipment member.

Re alloy coating for diffusion barrier

Disclosed is a ReCrNi alloy coating for diffusion barrier, such as a high-temperature equipment member, consisting essentially of a ternary alloy and having, except for inevitable impurities, an atomic composition of 20% to 80% Re, an atomic composition of 20% to 60% Cr, and an atomic composition of 5% to 40% Ni. Even if the alloy coating for diffusion barrier includes a diffusion layer containing at least one of the group consisting of Al, Si and Cr, a desired alloy composition of the alloy coating for diffusion barrier can be assured by a surface coating process and diffused components from the substrate while substantially preventing the diffusion of the elements of the diffusion layer during a homogenizing heat treatment. The alloy coating for diffusion barrier may include a Re-containing-alloy stress relief layer inserted between the film and the substrate. The ReCrNi alloy coating can suppress the deterioration of the substrate and the coating layer due to the reaction therebetween to provide an extended life span of the equipment member.

ReCrNi alloy coating for diffusion barrier

Discloses is a metal-based resistance heat-generation element. The element comprises a core made of a platinum group metal or refractory metal, and a coating film formed on the core. The coating film has at least two layers including a core-side inner layer of a Re&#x2014;Cr based &#x3c3; (sigma) phase and a surface-side outermost layer of an aluminide or silicide. Alternatively, the element may comprise a core made of an alloy containing a platinum group metal or refractory metal and Re and Cr diffused therein, and a coating film formed on the core. The coating film has at least one layer including an aluminide or silicide layer.

Metal based resistance heating element and method for preparation therefor

Disclosed is a heat-resistant Ti alloy material excellent in high-temperature corrosion resistance and oxidation resistance, which comprises a base made of a heat-resistant Ti alloy and a surface layer formed on the surface of the base. The surface layer has a multilayer structure including an inner layer and an outer layer. The inner layer has three coexistent phases consisting of a &#x3b2; phase, a &#x3b3; phase and a Laves phase in the phase diagram of a Ti&#x2014;Al&#x2014;Cr based alloy, and the outer layer is made of an Al&#x2014;Ti&#x2014;Cr based alloy having an Al concentration of 50 atomic % or more. The heat-resistant Ti alloy material is produced by subjecting a substrate made of a heat-resistant Ti alloy to a Cr diffusion treatment at a temperature within a &#x3b2; single-phase region in the phase diagram of a Ti&#x2014;Al&#x2014;Cr based alloy, precipitating a &#x3b3; phase and a Laves phase from the &#x3b2; phase during a cooling process to form the inner layer with three coexistent phases consisting of the &#x3b2;, &#x3b3; and Laves phases, and then subjecting the obtained product to an Al diffusion treatment to form the outer layer. The heat-resistant Ti alloy material can prevent the diffusion of Al from the outer layer to the base and the diffusion of elements of the base to the outer layer while forming a protective AlOfilm in a self-repairing manner, to provide excellent high-temperature corrosion resistance and oxidation resistance to the heat-resistant Ti alloy base.

Heat-resistant Ti alloy material excellent in resistance to corrosion at high temperature and to oxidation

Disclosed is a ReCr alloy coating for diffusion barrier formed on a substrate, such as a high-temperature equipment member, which comprises an atomic composition of 50% to less than 90% Re, with the remainder consisting essentially of Cr except for inevitable impurities. Even if the alloy coating for diffusion barrier includes a diffusion layer containing at least one of the group consisting of Al, Si and Cr, a desired alloy composition of the alloy coating for diffusion barrier can be assured by a surface coating process and diffused components from the substrate while substantially preventing the diffusion of the elements of the diffusion layer during a homogenizing heat treatment. The alloy coating for diffusion barrier may include a Re-containing-alloy stress relief layer inserted between the film and the substrate. The ReCr&#x2014;Ni alloy coating can suppress the deterioration of the substrate and the coating layer due to the reaction therebetween to provide an extended life span of the equipment member.

ReCr alloy coating for diffusion barrier

Disclosed is a method for forming a Re&#x2014;Cr alloy film consisting of Re in the range of 60 to 90% by atomic composition. The method comprises performing an electroplating process using an electroplating bath containing an aqueous solution which includes a perrhenate ion and a chromium (VI) ion. The present invention allows a Re&#x2014;Cr alloy film usable as a corrosion-resistant alloy coating for a high-temperature component or the like to be formed through an electroplating process using an aqueous solution, so as to provide heat/corrosion resistances to the component, even if it has a complicated shape, in a simplified manner at a low cost.

Method for forming Re-Cr alloy film through electroplating process using bath containing Cr(VI)

Disclosed is a method for forming: a Re&#x2014;Cr alloy film consisting of Re in the range of greater than 0 (zero) to less than 98% by atomic composition, and the remainder being Cr except inevitable impurities; a Re-based film consisting of 98% or more, by atomic composition, of Re, with the remainder being Cr and inevitable impurities; or a Re&#x2014;Cr&#x2014;Ni alloy film consisting of Re in the range of 50 to less than 98% by atomic composition, Cr in the range of 2 to less than 45% by atomic composition, and the remainder being Ni except inevitable impurities. The method comprises performing an electroplating process using an electroplating bath containing an aqueous solution which includes a perrhenate ion and a chromium (III) ion. The present invention allows a Re&#x2014;Cr alloy, Re-based or Re&#x2014;Cr&#x2014;Ni alloy film usable as a corrosion-resistant alloy coating for a high-temperature component or the like to be formed through an electroplating process using an aqueous solution, so as to provide heat/corrosion resistances to the component, even if it has a complicated shape, in a simplified manner at a low cost.

Method for forming Re&#x2014;Cr alloy film or Re-based film through electroplating process

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.

Growing community of inventors

Hokkaido, Japan

Toshio Narita