Hitachi, Ltd.

Mitsubishi Hitachi Power Systems, Ltd.

Hitachi Engineering Co., Ltd.

Other

Japan Science and Technology Agency

Hitachi Metals, Ltd.

Renesas Technology Corp.

Tohoku University

Hitachi Ulsi Systems Co., Ltd.

Hitachi Usli Systems Co., Ltd.

Jun Sato

Shinya Imano

Shigeru Matsuo

Koyo Katsura

Takashi Sone

Takashi Miyamoto

Hiroyuki Doi

Kazushige Yamagishi

Masahiko Kikuchi

Kazushige Ayukawa

Yoshikazu Yokota

Kiyohito Ishida

Takao Watanabe

Kazumasa Yanagisawa

Toshio Sasaki

Hitoshi Tanaka

Yuji Tanaka

Ryosuke Kainuma

Ikuo Ohnuma

Satoru Nakanishi

Mariko Ohtsuka

Masakatu Yokoyama

Tomonori Ueno

Takashi Shibayama

Eiji Shimohira

Katunari Oikawa

Shinichi Kobayashi

Kenichi Murata

Hiroshi Takeda

Yasuhiro Nakatsuka

Hiroyuki Hamasaki

Shinichi Fujino

Satoshi Hirano

Takehiro Ohno

Toshihiro Omori

Yutaka Sato

Chuya Aoki

Hidetoshi Kuroki

Seunghwan Park

Katsunari Oikawa

Sadashi Seto

Hironori Kamoshida

Kazuhiro Hirade

Isamu Mochizuki

Eiji Nishioka

Makoto Takano

Hiroyuki Kokawa

Yasuhiko Hoshi

Kenichiro Omura

Toshio Namatame

Toshihiro Ohmori

Kazuhiko Endo

Ryuichi Murashima

Nasakatu Yokoyama

There is provided a method for producing a Ni-based heat-resistant superalloy a primary &#x3b3;' phase with an average particle size of at least 500 nm comprising the steps of: providing a material to be hot-worked having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities; heating the material to be hot-worked in a temperature having a range of 1,130 to 1,200&#xb0; C. for at least 2 hours; cooling the material to be hot-worked heated by the heating step to a hot working temperature or less at a cooling rate of at most 0.03&#xb0; C./second; and subjecting the material to be hot-worked to hot working after the cooling step.

Ni-based heat-resistant superalloy and method for producing the same

A Ni-based alloy for a welding material including, by mass, 0.001 to 0.1% of C, 18 to 25% of Co, 16 to 20% of Cr, 2.5 to 3.5% of Al, 9.0 to 15.0% of Mo+W, 0.001 to 0.03% of B and the balance being Ni and inevitable impurities.

Ni-based alloy for welding material and welding wire, rod and power

There are provided a precipitation strengthening type martensitic steel having both a tensile strength of a 1500 MPa class and a high Charpy absorption energy of 30 J or higher, and a manufacturing process thereof. The precipitation strengthening type martensitic steel includes, in terms of mass %, 0.05% or less of C, 0.2% or less of Si, 0.4% or less of Mn, 7.5 to 11.0% of Ni, 10.5 to 13.5% of Cr, 1.75 to 2.5% of Mo, 0.9 to 2.0% of Al, less than 0.1% of Ti, and a remainder of Fe and impurities, and contains 0.1 to 6.0% of austenite in terms of a volume fraction.

Process for producing precipitation strengthening martensitic steel

An Ni base forged alloy is easy to make hot forging and miniaturization of crystal grains while excellent high-temperature strength and segregation property are compatible. The Ni base forged alloy has solid solution temperature of a precipitation strengthening phase lower than or equal to 970&#xb0; C., difference in the solid solution temperature between a &#x3b4;-phase and the precipitation strength phase larger than or equal to 50&#xb0; C., Al of 0.5 to 1.0%, Cr of 17 to 21%, Fe of 17 to 19%, Nb of 4.5 to 5.5%, Ti of 0.8 to 1.3%, W of 3.0 to 6.0%, B of 0.001 to 0.03%, C of 0.001 to 0.1% and Mo of 1.0% or less in mass percentage [%] and remainder made of Ni and inevitable impurities.

Ni base forged alloy and gas turbine utilizing the same

A turbine rotor includes a high- and low-temperature side rotor base materials. The high- and low-temperature materials include concavities and grooves. The turbine rotor has an enclosed space formed by the concavity of the high- and low-temperature materials being disposed opposingly, and a gap formed by the grooves of the high- and low-temperature materials being disposed opposingly. The turbine rotor contains a buildup welding section formed between the high- and low-temperature materials, which has the same composition as that of the high- or low-temperature material, and has a penetration bead on the enclosed space side, and the gap contains a weld metal filled therein. Thus, a stable penetration bead can be formed in a dissimilar material welded rotor combining two kinds of alloy materials with different thermal properties, and then generation of a non-welded portion of a butting section that becomes a start point of fracture can be suppressed.

Turbine rotor, manufacturing method thereof and steam turbine using turbine rotor

A nickel (Ni) based alloy for forging includes: 0.001 to 0.1 wt. % of carbon (C); 12 to 23 wt. % of chromium (Cr); 3.5 to 5.0 wt. % of aluminum (Al); 5 to 12 combined wt. % of tungsten (W) and molybdenum (Mo) in which the Mo content is 5 wt. % or less; a negligible small amount of titanium (Ti), tantalate (Ta) and niobium (Nb); and the balance of Ni and inevitable impurities.

Nickel based alloy for forging

A high-temperature piping product is configured from a plurality of primary pipe members and a welding material. The primary pipe members are each made from an Ni-based forged alloy containing: Ni, Al, and at least one of Mo and W. The total content of the Mo and the W being 3-8 mass %. The Ni-based forged alloy exhibiting a &#x3b3;'-phase dissolution temperature of from 920 to 970&#xb0; C., and the &#x3b3;&#x2032; phase being precipitated in 30 volume % or more in a temperature range of from 700 to 800&#xb0; C. The welding material is made from an Ni-based cast alloy having a cast structure formed by welding. The Ni-based cast alloy containing: Ni, Al, and at least one of Mo and W, the total content of the Mo and the W being 9-15 mass %, the Ni-based cast alloy exhibiting a &#x3b3;&#x2032;-phase dissolution temperature of from 850 to 900&#xb0; C.

High-temperature piping product and method for producing same

A process for producing a Co-base alloy which has a basic composition including, in terms of mass proportion, 0.1%-10% Al, 3.0-45% W, and Co as the remainder and has an intermetallic compound of the L1type [Co(Al,W)] dispersed and precipitated therein. Part of the Co may be replaced with Ni, Ir, Fe, Cr, Re, or Ru, while part of the Al and W may be replaced with Ni, Ti, Nb, Zr, V, Ta or Hf. The intermetallic compound [Co(Al, W)] has a high melting point, and this compound and the matrix are mismatched little with respect to lattice constant. Thus, the cobalt-base alloy can have high-temperature strength equal to that of nickel-base alloys and excellent structure stability.

Cobalt-base alloy with high heat resistance and high strength and process for producing the same

Disclosed are a high-strength Ni-base alloy, a method of producing the Ni-base alloy, and a method of recovering a member made of a degraded Ni-base alloy. It contains not more than 0.1 wt % C, not more than 50 wt % Fe, not more than 30 wt % Cr, Ti, and at least one of Nb and Al. It has been strengthened by precipitates of a &#x3b3;' phase (NiAl) and/or a &#x3b3;&#x2033; phase (NiNb). It contains also a &#x3b7; phase (NiTi) which is thermodynamically stable in a temperature range of 800&#xb0; C. to 900&#xb0; C. When observed a cross-section of the Ni-base alloy, a plurality of nodes exist along each segment connecting two meeting points each of which point is defined by adjacent three crystal grains, and precipitates of the &#x3b3;&#x2032; phase and/or the &#x3b3;&#x2033; phase in each of crystal grains of the Ni-base alloy have an average particle size of not more than 100 nm.

Ni-base alloy and method of producing the same

The present invention provides, in a &#x3b3;' phase precipitation strengthening type Ni-base alloy, an alloy excellent in heat treatment capability and weldability and suitable for joint with a ferritic steel. Further, the present invention provides a welded turbine rotor having the strength, ductility, and toughness simultaneously over the whole welded structure when a precipitation strengthening type Ni-base alloy having a heatproof temperature of 675&#xb0; C. or higher is joined to a ferritic steel. A Ni-base alloy according to the present invention contains cobalt, chromium, aluminum, carbon, boron, and at least either tungsten or molybdenum with the remainder being nickel and inevitable impurities, having an alloy composition including 12 to 25 percent by mass of Co, 10 to 18 percent by mass of Cr, 2.0 to 3.6 percent by mass of Al, 0.01 to 0.15 percent by mass of C, 0.001 to 0.03 percent by mass of B, the total amount of tungsten and molybdenum being 5.0 to 10 percent by mass. A welded turbine rotor is structured by joining or building up by welding a second Ni-base alloy to a first Ni-base alloy that a &#x3b3;&#x2032; phase solid solution temperature thereof is 900&#xb0; C. or higher and a creep fracture strength at 675&#xb0; C. is 100 MPa or more, and further welding a ferritic steel to the second Ni-base alloy. The second Ni-base alloy is a &#x3b3;&#x2032; phase (NiAl) precipitation strengthening type Ni-base alloy, a &#x3b3;&#x2032; phase solid solution temperature thereof is 850&#xb0; C. or lower.

Ni-base alloy, high-temperature member for steam turbine and welded rotor for turbine using the same, and method for manufacturing the same

It is an objective of the invention to provide a Ni-based forged alloy having good large ingot formability and good hot formability as well as high mechanical strength at high temperature. There is provided a Ni-based forged alloy comprising: 0.001 to 0.1 mass % of C; 0.001 to 0.01 mass % of B; 16 to 22 mass % of Cr; 0.5 to 1.5 mass % of Al; 0.1 to 6.0 mass % of W; 3.5 to 5.5 mass % of Nb; 0.8 to 3.0 mass % of Ti; 16 to 20 mass % of Fe; 2.0 mass % or less of Mo; and the balance including Ni and unavoidable impurities, in which: a segregation parameter Ps defined by a formula of 'Ps (mass %) =1.05&#xd7;[Al concentration (mass %)]+0.6&#xd7;[Ti concentration (mass %)]&#x2212;0.8&#xd7;[Nb concentration (mass %)]&#x2212;0.3&#xd7;[Mo concentration (mass %)]' satisfies a relationship of 'Ps&#x2267;&#x2212;3.0 mass %'; and a total amount of W and Mo is 1.75 atomic % or less.

Nickel based forged alloy, gas turbine member using said alloy and gas turbine using said member

A Ni-based heat resistant alloy has a composition of, by mass percent, carbon: 0.001 to 0.1%, chromium: 16 to 22%, aluminum: 0.5 to 1.5%, molybdenum: 0.1 to 2.0%, tungsten: 0.1 to 6.0%, niobium: 3.5 to 5.5%, titanium: 0.8 to 3.0%, iron: 16 to 20%, and the balance being nickel and inevitable impurities. A parameter Ps indicating a segregation tendency is in a range of Ps&#x2267;&#x2212;3.5. The parameter Ps is represented by Formula (1).Ps=1.05&#xd7;Al content+0.6&#xd7;Ti content&#x2212;0.8&#xd7;Nb content&#x2212;0.3&#xd7;Mo content&#x2003;&#x2003;(1)

Ni-based heat resistant alloy, gas turbine component and gas turbine

A Co-base alloy which has a basic composition including, in terms of mass proportion, 0.1%-10% Al, 3.0-45% W, and Co as the remainder and has an intermetallic compound of the Lltype [Co(Al,W)] dispersed and precipitated therein. Part of the Co may be replaced with Ni, Ir, Fe, Cr, Re, or Ru, while part of the Al and W may be replaced with Ni, Ti, Nb, Zr, V, Ta or Hf. The intermetallic compound [Co(Al, W)] has a high melting point, and this compound and the matrix are mismatched little with respect to lattice constant. Thus, the cobalt-base alloy can have high-temperature strength equal to that of nickel-base alloys and excellent structure stability.

A nickel base alloy includes: by mass, 0.001 to 0.1% of carbon; 12 to 23% of chromium; 15 to 25% of cobalt; 3.5 to 5.0% of aluminum; 4 to 12% of molybdenum; 0.1 to 7.0% of tungsten; and a total amount of Ti, Ta and Nb being not more than 0.5%. A parameter Ps represented by a formula (1) shown below is 0.6 to 1.6,=&#x2212;7&#xd7;[C]&#x2212;0.1&#xd7;[Mo]+0.5&#xd7;[Al]&#x2003;&#x2003;(1)where [C] indicates an amount of carbon; [Mo] indicates an amount of molybdenum; and [Al] indicates an amount of aluminum, by mass percent.

Nickel base wrought alloy

Growing community of inventors

Hitachi, Japan

Jun Sato