Abstract: Provided is a steel sheet for hot stamping having a predetermined chemical composition and a metallographic structure comprising, by area ratio, ferrite: 10% or more and pearlite: 10% or more, wherein a total of ferrite and pearlite is 80% or more, and a dispersion index of pearlite is 0.50 or more. Further, provided is a hot stamped part having a predetermined chemical composition and a metallographic structure comprising, by area ratio, at least one of martensite, bainite, and tempered martensite in a total of 90% or more, wherein a standard deviation in a hardness distribution of prior austenite grains at a sheet thickness ¼ position is 150 Hv or less.

Abstract: This steel sheet for hot stamping has a predetermined chemical composition and has a microstructure in which S?+SGB, which is a total of an area ratio S? of ferrite and an area ratio SGB of a granular bainite, is 10% or more and less than 50% and SGB/S?, which is a ratio between the area ratio SGB of the granular bainite and the area ratio S? of the ferrite, is 0.30 to 0.70. In addition, a hot-stamping formed body manufactured using this steel sheet for hot stamping has a predetermined chemical composition and a microstructure in which an average grain size of prior austenite grains is 5 to 25 ?m, and a standard deviation of grain sizes of the prior austenite grains is 0.1 to 2.0 ?m, and a tensile strength of the hot-stamping formed body is 2,200 MPa or more.

Abstract: This hot-stamping formed body has a predetermined chemical composition and has a microstructure in which an average grain size of prior austenite grains is 5 to 25 ?m, and a standard deviation of grain sizes of the prior austenite grains is 0.1 to 2.0 ?m. In addition, this steel sheet for hot stamping has a predetermined chemical composition and has a microstructure in which an average value of the pole densities of ferrite in the orientation group consisting of {100}<011> to {223}<110> is 10.0 or less, in entire ferrite, a number proportion of ferrite containing a carbide having an equivalent circle diameter of 0.2 ?m or more in grains is 20% or more, and the steel sheet for hot stamping has a microstructure in which an area ratio of pearlite is 10% to 90% and an ratio of ferrite is 10% to 90%.

Abstract: A flow path switching valve includes a rotatable portion, a packing portion and a valve main body. The valve main body includes: a valve chamber that receives the rotatable portion and the packing portion; an inflow hole; and an outflow hole. The packing portion is configured to be positioned at a predetermined position, at which the packing portion closes an outflow-hole opening end of the outflow hole, in response to rotation of the rotatable portion. When the packing portion is positioned at the predetermined position, the packing portion is urged against a main-body seal portion in a radial direction of a valve axis by a pressure of fluid in the valve chamber, which is higher than a pressure in the outflow hole.

Abstract: Provided is a surface layer grain refining hot-shearing method including: heating and keeping a steel sheet in a temperature range of from Ac3 to 1400° C. to austenitize the steel sheet; subsequently shearing the steel sheet in a state in which the steel sheet is placed on a die; and quenching by rapidly cooling the sheared steel sheet, wherein a start temperature of the shearing is set to be a temperature (° C.) obtained by adding a temperature of from 30° C. to 140° C. to a previously measured Ar3 of the steel sheet.

Abstract: The present invention provides a steel wire, including chemical components of: C: 0.7-1.2 mass %; Si: 0.05-2.0 mass %; and Mn: 0.2-2.0 mass %, with a balance including Fe and inevitable impurities, in which the steel wire has a pearlite structure, the average C concentration at a center portion of a ferrite phase in an outermost layer of the steel wire is 0.2 mass % or lower, and a residual compressive stress in the longitudinal direction of the steel wire in the outermost layer is 600 MPa or more.

Abstract: A cutting method for cutting a workpiece by using a cutting blade. The cutting method includes the steps of attaching an adhesive sheet to one surface of the workpiece, holding the workpiece through the adhesive sheet on holding means, and feeding the cutting blade into the workpiece until reaching the adhesive sheet as supplying a cutting fluid having a temperature of 10° C. or less, thereby cutting the workpiece.

Abstract: A power control apparatus includes an inverter giving a rectangular waveform drive signal to an induction motor, an inverter voltage controlling section controlling an output voltage of the inverter, a converter boosting a voltage supplied to the inverter, a converter voltage controlling section controlling an output voltage of the converter, and a control signal generating section that controls the inverter voltage controlling section in a low-rotational speed region and controls the converter voltage controlling section in a high-rotational speed region.

Abstract: A power control apparatus includes an inverter giving a rectangular waveform drive signal to an induction motor, an inverter voltage controlling section controlling an output voltage of the inverter, a converter boosting a voltage supplied to the inverter, a converter voltage controlling section controlling an output voltage of the converter, and a control signal generating section that controls the inverter voltage controlling section in a low-rotational speed region and controls the converter voltage controlling section in a high-rotational speed region.

Abstract: A three-wave rectifying unit of an AC generator has a plus-side cooling fin, a minus-side cooling fin and a DC-output terminal. The DC-output terminal is made of a metal plate which is harder than the plus-side cooling fin to provide tight mechanical connection. The DC-output terminal, the plus-side cooling fin, a plus-side brush terminal and a plus-side terminal of a voltage regulator are fastened together and electrically connected by a screw which is screwed into a portion of the DC-output terminal.

Abstract: A stack of two different metals to be welded, one of which is harder than the other, and an additional soft metal placed on the harder metal is placed between a pair of horn tips (grip members) of an ultrasonic welder. The harder metal is covered with a soft metal layer of a high plastic fluidity. Serrations are formed on the surface of the horn tips to grip the softer metal and the additional metal tightly during ultrasonic vibration is applied.