Abstract: Provided is a case hardening steel which allows effective inhibition of abnormal grain growth during carburizing treatment or the like and makes it possible to solve the problem of abnormal grain growth-induced reduction in characteristics. In the case hardening steel, a total amount of TiC, ZrC and AlN which are precipitate particles contained in 100 g of a steel material after subjecting the case hardening steel to hot rolling is 3.5×10?4 mole or less.

Abstract: The present invention relates to a maraging steel containing, in terms of mass %, 0.20?C?0.35, 9.0?Co?20.0, 1.0?(Mo+W/2)?2.0, 1.0?Cr?4.0, and a certain amount of Ni, with the balance being Fe and inevitable impurities, in which in a case where the contents of V and Nb satisfy V+Nb?0.020 mass %, the amount of Ni is 6.0?Ni?9.4, and in which in a case where the contents of V and Nb satisfy 0.020 mass %<V+Nb?0.60 mass %, the amount of Ni is 6.0?Ni?16.0.

Abstract: The present invention relates to a method for producing a precipitation strengthened Ni-based superalloy material having a predetermined composition, containing a blooming forging step of performing a forging at a temperature range of from Ts to Tm and performing an air cooling to form a billet having an average crystal grain size of #1 or more, an overaging thermal treatment step of heating and holding the billet at a temperature range of from Ts to Ts+50° C. and slowly cooling it to a temperature of Ts or lower, and a crystal grain fining forging step of performing another forging at a temperature range of from Ts?150° C. to Ts and performing another air cooling, in which Ts is from 1,030° C. to 1,100° C., and an overall average crystal grain size is #8 or more after the crystal grain fining forging step.

Abstract: The present invention relates to an electric arc furnace, containing a furnace shell, an electrode, a furnace shell moving mechanism that supports the furnace shell so as to be movable on an installation surface, and a first insulation that electrically insulates between the furnace shell and the furnace shell moving mechanism.

Abstract: The present invention relates to a method of operating an electric arc furnace containing (a) a furnace shell having a tapping hole and/or a slag door, (b) a furnace roof having a plurality of electrodes provided so as to face downwards, and (c) a rotating apparatus that rotates the furnace shell around a vertical axis relative to the electrodes, the method contains a rotating step of rotating the furnace shell relative to the electrodes during melting of a metal material, and a holding step of stopping the rotation when any one of the plurality of electrodes reaches a holding position that is previously set close to the tapping hole or the slag door, and holding the furnace shell at the holding position.

Abstract: The present invention relates to a steel for a mold, having a composition containing, on a % by mass basis, 0.25%<C<0.38%, 0.01%<Si<0.30%, 0.92%<Mn<1.80%, 0.8%<Cr<2.2%, 0.8%<Mo<1.4%, and 0.25%<V<0.58%, with the balance being Fe and inevitable impurities, and a mold manufactured by additive manufacturing by using the steel for a mold.

Abstract: Provided is a maraging steel excellent in fatigue characteristics, including, in terms of % by mass: C: ?0.015%, Ni: from 12.0 to 20.0%, Mo: from 3.0 to 6.0%, Co: from 5.0 to 13.0%, Al: from 0.01 to 0.3%, Ti: from 0.2 to 2.0%, O: ?0.0020%, N: ?0.0020%, and Zr: from 0.001 to 0.02%, with the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to an Ni-based superalloy for hot forging, containing, in terms of % by mass, C: more than 0.001% and less than 0.100%, Cr: 11% or more and less than 19%, Co: more than 5% and less than 25%, Fe: 0.1% or more and less than 4.0%, Mo: more than 2.0% and less than 5.0%, W: more than 1.0% and less than 5.0%, Nb: 2.0% or more and less than 4.0%, Al: more than 3.0% and less than 5.0%, and Ti: more than 1.0% and less than 3.0%, with the balance being unavoidable impurities and Ni, in which the component composition satisfies the following two relationships: 3.5?([Ti]+[Nb])/[Al]×10<6.5 and 9.5?[Al]+[Ti]+[Nb]<13.0.

Abstract: The present invention relates to a method for manufacturing a sintered magnet, using a mold provided with a main body having a cavity and a lid whose inner face is flat, and the method containing a filling process of filling alloy powder in the cavity and then mounting the lid on the main body, an orienting process of applying a magnetic field in a predetermined direction to the alloy powder in a state of being filled in the cavity, a sintering process of sintering the alloy powder by heating in a state of being filled in the cavity after the orienting process, and a mold inverting process of turning the mold upside down which is carried out between the filling process and the orienting process or between the orienting process and the sintering process.

Abstract: The mold steel according to the present invention contains 0.35<C<0.55 mass %, 0.003?Si<0.300 mass %, 0.30<Mn<1.50 mass %, 2.00?Cr<3.50 mass %, 0.003?Cu<1.200 mass %, 0.003?Ni<1.380 mass %, 0.50<Mo<3.29 mass %, 0.55<V<1.13 mass %, and 0.0002?N<0.1200 mass %, with a balance being Fe and unavoidable impurities, and satisfies 0.55<Cu+Ni+Mo<3.29 mass %, and the molding tool according to the present invention contains a mold and/or a mold component formed of the mold steel.

Abstract: A method of operating an electric arc furnace containing a furnace shell having a tapping hole, a plurality of electrodes, and a rotating apparatus that rotates the furnace shell around a vertical axis relative to the electrodes, the method contains a charging step of opening an opening-and-closing door of a scrap bucket containing a metal material and falling the metal material into the furnace shell in which the furnace shell is rotated by the rotating apparatus until a direction of a line connecting a center of the furnace shell to a center of the tapping hole intersects an extension direction of a seam at a closing side of the opening-and-closing door, the opening-and-closing door is opened in this positional relationship to charge the metal material.

Abstract: The present invention relates to a laminated body containing at least (a) a transparent substrate, (b) a first metal layer that is overlaid on the substrate and forms an electrode, and (c) a second metal layer having a light reflectance of 20% or less, in which the second metal layer is overlaid on the surface of the first metal layer opposite to the substrate or between the first metal layer and the substrate by sputtering using a reactive sputtering gas, and the second metal layer is constituted by an oxide or nitride of a Cu alloy containing at least Zn.

Abstract: A melting furnace is provided, that may contain a furnace shell, a furnace shell moving mechanism that supports the furnace shell so as to be movable on an installation surface, a pipe or a wiring that has one end fixed to the furnace shell and has at least partially, a flexible portion, and a stand. The stand may contain a supporting part that supports a halfway portion of the pipe or the wiring, and a stand moving part that is coupled to the supporting part and moves the supporting part on an installation surface in synchronization with movement of the furnace shell, in which the stand is mounted on the installation surface so as to be movable up and down with respect to the furnace shell.

Abstract: Provided is a combined type RFeB-based magnet, including: a first unit magnet; a second unit magnet; and an interface material that bonds the first unit magnet and the second unit magnet, in which the first unit magnet and the second unit magnet are RFeB-based magnets containing a light rare earth element RL that is at least one element selected from the group consisting of Nd and Pr, Fe, and B, in which the interface material contains at least one compound selected from the group consisting of a carbide, a hydroxide, and an oxide of the light rare earth element RL, and in which an amount of a heavy rare earth element RH that is at least one element selected from the group consisting of Dy, Tb and Ho in the second unit magnet is more than that in the first unit magnet.

Abstract: Disclosed are tools, systems, and methods for detecting one or more underground acoustic sources and localizing them in depth and radial distance from a wellbore, for example, for the purpose of finding underground fluid flows, such as may result from leaks in the well barriers. In various embodiments, acoustic-source detection and localization are accomplished with an array of at least three acoustic sensors disposed in the wellbore, in conjunction with array signal processing.

Abstract: The invention provides a carburized part which has excellent medium-cycle fatigue strength in particular subjected to surface-hardening treatment by carburization. The invention provides a carburized part including a carburized layer formed by performing carburizing treatment to a steel, the steel including, in terms of % by mass: 0.15% to 0.25% of C, 0.15% or less of Si, 0.4% to 1.1% of Mn, 0.8% to 1.4% of Cr, 0.25% to 0.55% of Mo, 0.015% or less of P, and 0.035% or less of S, with the remainder being Fe and unavoidable impurities, and the steel satisfying the following relation; 0.10?[Mo]/(10[Si]+[Mn]+[Cr])?0.40, in which [M] represents a content of element M in terms of % by mass.

Abstract: The present invention relates to a mold steel having a composition including, in terms of mass %: 0.220%?C?0.360%; 0.65%?Si<1.05%; 0.43%?Mn?0.92%; 0.43%?Ni?0.92%; 0.67%?0.5Mn+Ni?1.30%; 10.50%?Cr<12.50%; 0.05%?Mo<0.50%; 0.002%?V<0.50%; 0.001%?N?0.160%; and 0.300%?C+N?0.420%, with the remainder being Fe and unavoidable impurities.

Abstract: The object of the present invention is to provide a heat-resistant steel for exhaust valves, having relatively small Ni content, high mechanical characteristics (for example, tensile strength, fatigue strength, wear resistance and hardness) at high temperature, and excellent oxidation resistance. The present invention provides a heat-resistant steel for exhaust valves, which includes: 0.45?C<0.60 mass %, 0.30<N<0.50 mass %, 19.0?Cr<23.0 mass %, 5.0?Ni<9.0 mass %, 8.5?Mn<10.0 mass %, 2.5?Mo<4.0 mass %, 0.01?Si<0.50 mass %, and 0.01?Nb<0.30 mass %, with the balance being Fe and unavoidable impurities, in which the steel satisfies 0.02?Nb/C<0.70 and satisfies 4.5?Mo/C<8.9.

Abstract: Producing an RFeB system sintered magnet with high corrosion resistance and low loss of energy in an RFeB system sintered magnet with high magnetic properties produced by a grain boundary diffusion process. A paste prepared by mixing an organic matter having a molecular structure including an oxygen atom and a metallic powder containing a heavy rare-earth element which is at least one element selected from the group of Dy, Ho and Tb, is applied to the surface of an RFeB system sintered compact composed of crystal grains whose main phase is R2Fe14B containing, as a main rare-earth element, a light rare-earth element which is at least one element selected from the group of Nd and Pr. A heating process for a grain boundary diffusion treatment is performed. As a result, a protective layer containing an oxide of the light rare-earth element is formed on the surface.

Abstract: The present invention relates to a turbine wheel of an automotive turbocharger, including a Ni-based alloy having a composition which contains, in terms of mass %: C: 0.08 to 0.20%; Mn: 0.25% or less; Si: 0.01 to 0.50%; Cr: 12.0 to 14.0%; Mo: 3.80 to 5.20%; Nb+Ta: 1.80 to 2.80%; Ti: 0.50 to 1.00%; Al: 5.50 to 6.50%; B: 0.005 to 0.015%; Zr: 0.05 to 0.15%; and Fe: 0.01 to 2.5%, with the remainder being Ni and unavoidable impurities, in which the turbine wheel includes a wing part and a shaft part, and a size of ?? phase in each site of from a tip of the wing part to the shaft part is structure-controlled so as to fall within a range of from 0.4 to 0.8 ?m.