Abstract: The present invention provides a TiAl-based alloy, including: Al: 41 to 43 at %; Fe: 0 to 2.5 at %; Ni: 0 to 2.5 at %; Mo: 0 to 2.0 at %; W: 0 to 2.0 at %; Cr: 0 to 4.5 at %; Mn: 0 to 5.5 at %; V: 0 to 10 at %; Nb: 0 to 10 at %; C: 0.3 to 0.7 at %; and a remainder consisting of Ti and inevitable impurities, in which an alloy element parameter “P=(41.5?Al)/3+Fe+Ni+Mo+W+0.5 Cr+0.4 Mn+0.2 V+0.2 Nb—C” is in a composition range of 1.1 to 1.9, and the TiAl-based alloy has a microstructure consisting of a ? phase of 5 to 30 area %, a ? phase of 0.5 to 5 area %, and a lamellar structure occupying a remaining part.

Abstract: The present invention provides a TiAl-based alloy, including: Al: 41 to 43 at %; Fe: 0 to 2.5 at %; Ni: 0 to 2.5 at %; Mo: 0 to 2.0 at %; W: 0 to 2.0 at %; Cr: 0 to 4.5 at %; Mn: 0 to 5.5 at %; V: 0 to 10 at %; Nb: 0 to 10 at %; C: 0.3 to 0.7 at %; and a remainder consisting of Ti and inevitable impurities, in which an alloy element parameter “P=(41.5?Al)/3+Fe+Ni+Mo+W+0.5 Cr+0.4 Mn+0.2 V+0.2 Nb—C” is in a composition range of 1.1 to 1.9, and the TiAl-based alloy has a microstructure consisting of a ? phase of 5 to 30 area %, a ? phase of 0.5 to 5 area %, and a lamellar structure occupying a remaining part.

Abstract: A titanium alloy of the present invention includes aluminum at a ratio of 28.0 at % or more and 38.0 at % or less, iron at a ratio of 2.0 at % or more and 6.0 at % or less, and titanium and inevitable impurities as the balance or includes aluminum at a ratio of 28.0 at % or more and 38.0 at % or less, manganese at a ratio of 4.0 at % or more and 8.0 at % or less, and titanium and inevitable impurities as the balance. Further, the titanium alloy of the present invention may include silicon at a ratio of 0.3 at % or more and 1.5 at % or less.

Abstract: A titanium alloy of the present invention includes aluminum at a ratio of 28.0 at % or more and 38.0 at % or less, iron at a ratio of 2.0 at % or more and 6.0 at % or less, and titanium and inevitable impurities as the balance or includes aluminum at a ratio of 28.0 at % or more and 38.0 at % or less, manganese at a ratio of 4.0 at % or more and 8.0 at % or less, and titanium and inevitable impurities as the balance. Further, the titanium alloy of the present invention may include silicon at a ratio of 0.3 at % or more and 1.5 at % or less.

Abstract: Provided is a hot-forged TiAl-based alloy of the present invention containing 40 to 45 atom % of Al and additive elements in the following composition ratio (A) or (B), and the balance Ti with inevitable impurities: (A) Nb: 7 to 9 atom %, Cr: 0.4 to 4.0 atom %, Si: 0.3 to 1.0 atom %, and C: 0.3 to 1.0 atom %; and (B) at least one of Cr: 0.1 to 2.0 atom %, Mo: 0.1 to 2.0 atom %, Mn: 0.1 to 4.0 atom %, Nb: 0.1 to 8.0 atom %, and V: 0.1 to 8.0 atom %. The TiAl-based alloy is characterized by having a fine structure of densely arranged lamella grains that are laminated alternately with a Ti3Al phase (?2-phase) and a TiAl phase (?-phase) and have an average grain size of 1 to 200 ?m.

Abstract: An oxide particle dispersion-strengthened Ni-base superalloy includes Ni, 0.1% by weight to 14.0% by weight of Ru, 0.1% by weight to 14.0% by weight of Al, and inevitable impurities and has a crystal structure containing 0.01% by weight to 3.0% by weight of dispersed oxide particles based on the total amount of the superalloy.

Abstract: Provided is a hot-forged TiAl-based alloy of the present invention containing 40 to 45 atom % of Al and additive elements in the following composition ratio (A) or (B), and the balance Ti with inevitable impurities: (A) Nb: 7 to 9 atom %, Cr: 0.4 to 4.0 atom %, Si: 0.3 to 1.0 atom %, and C: 0.3 to 1.0 atom %; and (B) at least one of Cr: 0.1 to 2.0 atom %, Mo: 0.1 to 2.0 atom %, Mn: 0.1 to 4.0 atom %, Nb: 0.1 to 8.0 atom %, and V: 0.1 to 8.0 atom %. The TiAl-based alloy is characterized by having a fine structure of densely arranged lamella grains that are laminated alternately with a Ti3Al phase (?2-phase) and a TiAl phase (?-phase) and have an average grain size of 1 to 200 ?m.

Abstract: The oxide matrix composite material is obtained by subjecting a fiber composed of at least one oxide or complex oxide and a matrix composed of at least one oxide or complex oxide to composite formation. For the fiber and the matrix, a component composition is selected such that the fiber and the matrix keep thermodynamic equilibrium to each other in a temperature range not exceeding the melting temperature, and a fiber diameter of the fiber at the time of equilibrium keeps ½ or more of a fiber diameter of the fiber at the start of the composite formation.

Abstract: A hot-forged TiAl-based alloy having excellent oxidation resistance and high strength at high temperatures, and a process for producing such an alloy. A TiAl-based alloy comprising Al: (40+a) atomic % and Nb: b atomic %, with the remainder being Ti and unavoidable impurities, wherein a and b satisfy formulas (1) and (2) below. 0?a?2??(1) 3+a?b?7+a??(2) Also, a TiAl-based alloy comprising Al: (40+a) atomic % and Nb: b atomic %, and further comprising one or more elements selected from the group consisting of V: c atomic %, Cr: d atomic % and Mo: e atomic %, with the remainder being Ti and unavoidable impurities, wherein a to e satisfy formulas (3) to (9) shown below. 0?a?2??(3) 3+a?b+1.0c+1.8d+3.

Abstract: A TiAl based alloy having excellent strength as well as an improvement in toughness at room temperature, in particular an improvement in impact properties at room temperature, and a production method thereof, and a blade using the same are provided. This TiAl based alloy has a microstructure in which lamellar grains having a mean grain diameter of from 1 to 50 ?m are closely arranged. The alloy composition is Ti-(42-48)Al-(5-10)(Cr and/or V) or Ti-(38-43)Al-(4-10)Mn. The alloy can be obtained by subjecting the alloy to high-speed plastic working in the cooling process, after the alloy has been held in an equilibrium temperature range of the ? phase or the (?+?) phase.

Abstract: Provided are a method of manufacturing a brazed rotor composed of a wheel and a shaft joined to the former by brazing, having a durability and a reliability which can be enhanced without increasing the manufacturing man hours, and a turbine rotor for an exhaust turbo-supercharger. The wheel having a disc portion formed at its outer periphery with blades, and a rod-like shaft are arranged in a furnace, being opposed to each other at their surfaces to be joined with a brazing solder being interposed therebetween, and infrared radiation is irradiated onto a side part of the wheel so as to heat the surfaces to be joined up to a temperature in a range from 1,000 to 1,080 deg. C. in order to melt the brazing solder, thereby the wheel and the shaft are joined by brazing to each other at their surfaces to be joined.

Abstract: A TiAl based alloy having excellent strength as well as an improvement in toughness at room temperature, in particular an improvement in impact properties at room temperature, and a production method thereof, and a blade using the same are provided. This TiAl based alloy has a microstructure in which lamellar grains having a mean grain diameter of from 1 to 50 &mgr;m are closely arranged. The alloy composition is Ti-(42-48)Al-(5-10) (Cr and/or V) or Ti-(38-43)Al-(4-10)Mn. The alloy can be obtained by subjecting the alloy to high-speed plastic working in the cooling process, after the alloy has been held in an equilibrium temperature range of the &agr; phase or the (&agr;+&bgr;) phase.

Abstract: A TiAl based alloy having excellent strength as well as an improvement in toughness at room temperature, in particular an improvement in impact properties at room temperature, and a production method thereof, and a blade using the same are provided. This TiAl based alloy has a microstructure in which lamellar grains having a mean grain diameter of from 1 to 50 &mgr;m are closely arranged. The alloy composition is Ti-(42-48)Al-(5-10) (Cr and/or V) or Ti-(38-43)Al-(4-10)Mn. The alloy can be obtained by subjecting the alloy to high-speed plastic working in the cooling process, after the alloy has been held in an equilibrium temperature range of the &agr; phase or the (&agr;+&bgr;) phase.

Abstract: A titanium aluminum intermetallic compound based alloy superior in creep strength and low cycle fatigue strength made by casting. The alloy has lamellar structure. A volume ratio of non-lamellar structure of the alloy is equal to or less than 3 volume percent. Diameters of lamellar grains included in the alloy are equal to or less than 200 &mgr;m. Lamellar spacing of the lamella structure included in the alloy is equal to or less than 2 &mgr;m.

Abstract: An object of the present invention is to provide a weld material which contains 8 to 13% Cr, and can be used with the GMA welding method, a GMA welding method which has superior arc stability and can provide a welded material having superior properties, and a welded structure; in order to attain this object, a weld material is provided, which contains in weight, 0.01 to 0.15% C, 0.1 to 0.6% Si, 0.1 to 2.0% Mn, 8 to 13% Cr, 0.1 to 1.5% Ni, 0.3 to 2.0% Mo, 0.05 to 0.5% V, 0.08 to 0.5% W, 0.5 to 5.0% Co, 0.1 to 0.5% Ta, ≦0.08 N, 0.01 to 0.1% REMs, and consisting of the balance Fe with inevitable impurities.

Abstract: An object of the present invention is to provide a weld material which contains 8 to 13% Cr, and can be used with the GMA welding method, a GMA welding method which has superior arc stability and can provide a welded material having superior properties, and a welded structure; in order to attain this object, a weld material is provided, which contains in weight, 0.01 to 0.15% C, 0.1 to 0.6% Si, 0.1 to 2.0% Mn, 8 to 13% Cr,0.1 to 1.5% Ni, 0.3 to 2.0% Mo, 0.05 to 0.5% V, 0.08 to 0.5% W, 0.5 to 5.0% Co, 0.1 to 0.5% Ta, ≦0.08 N, 0.01 to 0.1% REMs, and consisting of the balance Fe with inevitable impurities.

Abstract: This invention relates to a TiAl intermetallic compound-based alloy exhibiting excellent heat resistance, oxidation resistance and resonance resistance and having a cast structure composed of fine equiaxed grains. Specifically, it relates to a TiAl intermetallic compound-based alloy comprising of 45 to 48 atomic percent of Al, 5 to 9 atomic percent of Nb, 1 to 2 atomic percent of Cr, 0.2 to 0.5 atomic percent of Si, 0.3 to 2 atomic percent of Ni, 0.01 to 0.05 atomic percent of Y, and the balance being Ti and incidental impurities, the alloy exhibiting excellent heat resistance, oxidation resistance and resonance resistance and having a cast structure formed of fine equiaxed grains.

Abstract: A TiAl based alloy having excellent strength as well as an improvement in toughness at room temperature, in particular an improvement in impact properties at room temperature, and a production method thereof, and a blade using the same are provided. This TiAl based alloy has a microstructure in which lamellar grains having a mean grain diameter of from 1 to 50 &mgr;m are closely arranged. The alloy composition is Ti-(42-48)Al-(5-10) (Cr and/or V) or Ti-(38-43)Al-(4-10)Mn. The alloy can be obtained by subjecting the alloy to high-speed plastic working in the cooling process, after the alloy has been held in an equilibrium temperature range of the &agr; phase or the (&agr;+&bgr;) phase.

Abstract: TiAl intermetallic compound-based alloys comprising Ti, Al, Nb and Cr and, if necessary, further comprising Ni and Co, which have excellent plastic workability, good resistance to oxidation at high temperatures, high strength or good creep resistance.