Abstract: The present invention relates to a steel material containing: 0.19 mass %?C?0.31 mass %; 0.010 mass %?V?0.180 mass %; Mn?1.50 mass %; 5.60 mass %?Cr?6.60 mass %; Cu+Ni?0.84 mass %; 0.60 mass %?Si?1.40 mass %; 0.60 mass %?Mo?2.00 mass %; 0.001 mass %?Al?0.080 mass %; and 0.003 mass %?N?0.040 mass %, with a balance being Fe and unavoidable impurities, in which the contents of Mn and Cr satisfy Mn/Cr>0.150.

Abstract: An amplifier device includes an amplifier including cascade-connected power amplifiers in a plurality of stages and a bias circuit configured to supply bias currents to the amplifier. A bias current supplied to a power amplifier in the first stage of the power amplifiers in the plurality of stages exhibits a positive temperature characteristic. A bias current supplied to a power amplifier in the final stage exhibits a negative temperature characteristic.

Abstract: The present invention relates to a steel material including: 0.25 mass %?C?0.37 mass %; 0.08 mass %?V?0.28 mass %; 6.60 mass %?Mn+Cr?7.40 mass %; Mn/Cr?0.150; Mn?0.60 mass %; Cr?6.60 mass %; Cu+Ni?0.84 mass %; 0.40 mass %?Si?0.90 mass %; 0.60 mass %?Mo?2.00 mass %; 0.001 mass %?Al?0.080 mass %; and 0.003 mass %?N?0.040 mass %, with the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to a steel for a mold, including 0.070?C?0.130 mass %, 0.01?Si?0.60 mass %, 0.02?Mn?0.60 mass %, 0.003?P?0.150 mass %, 0.005?Cu?1.50 mass %, 0.005?Ni?0.80 mass %, 7.50?Cr?8.40 mass %, 0.70?Mo?1.20 mass %, 0.01?V?0.30 mass %, 0.010?Al?0.120 mass %, and 0.015?N?0.095 mass %, with the balance being Fe and unavoidable impurities. The steel for a mold according to the present invention satisfies all of 6 properties of SA property, tempering hardness, residual stress, machinability, impact value and corrosion resistance.

Abstract: The present invention relates to a steel material including, in mass %: 0.310?C?0.410; 0.001?Si?0.35; 0.45?V?0.70; Cr?6.00; 6.25?Mn+Cr; Mn/Cr?0.155; Cu+Ni?0.84; 0.002?P?0.030; 0.0003?S?0.0060; P+5S?0.040; 2.03<Mo<2.40; 0.001?Al?0.050; and 0.003?N?0.050, with the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to a steel for a mold, having a composition containing, in mass %, 0.045?C?0.090, 0.01?Si?0.50, 0.10?Mn?0.60, 0.80?Ni?1.10, 6.60?Cr?8.60, 0.01?Mo?0.70, 0.001?V?0.200, 0.007?Al?0.150, and 0.0002?N?0.0500, with the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to a steel for a mold, including 0.070?C?0.130 mass %, 0.01?Si?0.60 mass %, 0.02?Mn?0.60 mass %, 0.003?P?0.150 mass %, 0.005?Cu?1.50 mass %, 0.005?Ni?0.80 mass %, 7.50?Cr?8.40 mass %, 0.70?Mo?1.20 mass %, 0.01?V?0.30 mass %, 0.010?Al?0.120 mass %, and 0.015?N?0.095 mass %, with the balance being Fe and unavoidable impurities. The steel for a mold according to the present invention satisfies all of 6 properties of SA property, tempering hardness, residual stress, machinability, impact value and corrosion resistance.

Abstract: The present invention relates to a steel for a mold, which has a composition containing, on % by mass basis: 0.35%?C?0.40%, 0.003%?Si?0.20%, 0.72%?Mn?0.94%, 5.65%?Cr?6.00%, 1.65%?Mo?2.00%, 0.71%?V?0.90%, and 0.001%?N?0.080%, with the balance being Fe and inevitable impurities.

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: Provided is a prehardened steel material containing: 0.05?C?0.25 mass %, 0.01?Si?1.00 mass %, 0.40?Mn?1.80 mass %, 0.0002?S?0.3000 mass %, 0.30?Cu?1.80 mass %, 2.00?Ni?3.90 mass %, 0.05?Cr?3.20 mass %, 0.05?Mo?0.80 mass %, and 0.30?Al?1.50 mass %, with a balance being Fe and unavoidable impurities, in which the prehardened steel material has: a cross-sectional size of 350 mm or more in width and 350 mm or more in height, a hardness of 34 to 43 HRC, an average value of prior austenite grain size being 85 ?m or less, and an average value of impact value being 18 J/cm2 or higher.

Abstract: The present invention provides an annealed steel material having a composition containing, in mass %, 0.28?C?0.42, 0.01?Si?1.50, 0.20?Mn?1.20, 4.80?Cr?6.00, 0.80?Mo?3.20, 0.40?V?1.20, and 0.002?N?0.080, with the balance being Fe and unavoidable impurities; in which the annealed steel material has a cross-sectional size of a thickness of 200 mm or more and a width of 250 mm or more, and a hardness of 100 HRB or less; and in which a diameter of a largest ferritic grain observed in a microstructure is 120 ?m or less in terms of a perfect circle equivalent, an area ratio of carbides is 3.0% or more and less than 10.5%, and an average particle diameter of the carbides is 0.18 ?m or more and 0.29 ?m or less.

Abstract: The present invention relates to a steel powder having a composition containing, in mass %, 0.10?C<0.25, 0.005?Si?0.600, 2.00?Cr?6.00, ?0.0125×[Cr]+0.125?Mn??0.100×[Cr]+1.800 in which the [Cr] represents the value of Cr content in mass %, 0.01?Mo?1.80, ?0.00447×[Mo]+0.010?V??0.1117×[Mo]+0.901 in which the [Mo] represents the value of Mo content in mass %, 0.0002?N?0.3000, and the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to a powder for additive manufacturing, having a composition consisting of, in mass %: 0.25<C<0.40, 0.001?Si?0.15, 0.30?Mn?0.45, 5.0?Cr?5.5, 1.0?Mo?1.5, 0.35?V?0.45, 0.01?N?0.05, 0.01?O?0.04, and optionally, P<0.10, Cu<0.20, Ni<0.20, Al<0.05, Zr<0.05, S<0.20, Pb<0.20, Bi<0.20, Nb<0.20, Ti<0.20, B<0.10, and Co<0.20, with the balance being Fe and unavoidable impurities, in which a surface of the powder for additive manufacturing is coated with an oxide film, and the oxide film has a thickness of 3 nm or more and 30 nm or less.

Abstract: The present invention relates to a steel and a mold constituted of the steel, in which the steel contains as essential elements, in terms of % by mass, 0.58%?C?0.70%, 0.010%?Si?0.30%, 0.50%?Mn?2.00%, 0.50%?Cr<2.0%, 1.8%?Mo?3.0%, and 0.050%<V?0.80%, with the balance being Fe and unavoidable impurities.

Abstract: The present invention relates to a steel for a mold, having a composition containing, in mass %, 0.045?C?0.090, 0.01?Si?0.50, 0.10?Mn?0.60, 0.80?Ni?1.10, 6.60?Cr?8.60, 0.01?Mo?0.70, 0.001?V?0.200, 0.007?Al?0.150, and 0.0002?N?0.0500, with the balance being Fe and unavoidable impurities.

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 present invention relates to a die-casting die, having a composition consisting of, in mass %: 0.16?C?0.26, 0.001?Si?0.80, 1.20?Mn?2.00, 2.41?Cr?2.73, 0.48?Mo?0.97, 0.003?V?0.28, 0.0005?Al?0.15, 0.0002?N?0.050, with the balance being Fe and unavoidable impurities, and having a hardness of 26 to 43 HRC and a thermal conductivity ? [W/m/K] measured by using a laser flash method at 25° C. being 27.0??.

Abstract: The present invention relates to a steel for a mold, which has a composition containing, on % by mass basis: 0.35%?C?0.40%, 0.003%?Si?0.20%, 0.72%?Mn?0.94%, 5.65%?Cr?6.00%, 1.65%?Mo?2.00%, 0.71%?V?0.90%, and 0.001%?N?0.080%, with the balance being Fe and inevitable impurities.

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 prehardened steel material containing: 0.05?C?0.25 mass %, 0.01?Si?1.00 mass %, 0.40?Mn?1.80 mass %, 0.0002?S?0.3000 mass %, 0.30?Cu?1.80 mass %, 2.00?Ni?3.90 mass %, 0.05?Cr?3.20 mass %, 0.05?Mo?0.80 mass %, and 0.30?Al?1.50 mass %, with a balance being Fe and unavoidable impurities, in which the prehardened steel material has: a cross-sectional size of 350 mm or more in width and 350 mm or more in height, a hardness of 34 to 43 HRC, an average value of prior austenite grain size being 85 ?m or less, and an average value of impact value being 18 J/cm2 or higher.