Abstract: Provided is a martensitic stainless-steel sheet having a reduced anisotropy in workability and fatigue resistance which are attributable to oxide based inclusions. A martensitic stainless-steel sheet which has a steel composition that contains, in terms of mass %, 0.030 to 0.300% C, 0.20 to 2.50% Si, 0.15 to 4.00% Mn, 0.01 to 1.00% Ni, 11.00 to 15.00% Cr, 0.001 to 0.100% N, 0.0001 to 0.0350% Al, 0 to 0.50% V, 0 to 0.50% Nb, 0 to 0.50% Ti, 0 to 0.020% B, and a balance of Fe and unavoidable impurities, and that has a value of ?max, determined by the following equation (1), of 80.0 or greater, and in which oxide based inclusions are observed in the metallographic structure, the oxide based inclusions having a converted composition comprising up to 30 mass % or less Al2O3, 20 to 60 mass % SiO2, and 15 to 70 mass % MnO.

Abstract: [Problem] To provide a raw material steel sheet for providing a high strength nonmagnetic austenitic stainless steel material that has a high elastic limit stress and excellent toughness. [Solution to Problem] An austenitic stainless steel sheet containing 0.12% or less of C, from 0.30 to 3.00% of Si, from 2.0 to 9.0% of Mn, from 7.0 to 15.0% of Ni, from 11.0 to 20.0% of Cr, and 0.30% or less of N, and further containing at least one kind of 3.0% or less of Mo, 1.0% or less of V, 1.0% or less of Nb, 1.0% or less of Ti, and 0.010% or less of B, all in terms of percentage by mass, with the balance of Fe and unavoidable impurities, having a component composition having a Ni equivalent of 19.0 or more, having a value of d?1/2 of 0.40 or more, wherein d (?m) represents an average austenitic crystal grain diameter, and having a property that provides a magnetic permeability ? of 1.0100 or less after subjected to cold rolling with an equivalent strain of 0.50 or more.

Abstract: A hot rolled austenitic stainless steel sheet contains 0.030 to 0.300% of C, from 0.30 to 3.20% of Si, from 0.90 to 17.00% of Mn, from 1.00 to 8.00% of Ni, from 14.00 to 19.00% of Cr, from 0.50 to 3.50% of Cu, from 0.045 to 0.250% of N, from 0.0001 to 0.0300% of Al, from 0 to 0.50% of V, from 0 to 0.50% of Nb, from 0 to 0.30% of Ti, and from 0 to 0.010% of B, all in terms of percentage by mass, with the balance of Fe and unavoidable impurities, has a converted average composition of an oxide based inclusion that contains 30% by mass or less of Al2O3, 60% by mass or less of SiO2, and 15% by mass or more of MnO, and satisfies MnO3—3SiO2+110. Anisotropy of workability and fatigue resistance characteristics caused by an oxide based inclusion is decreased.

Abstract: A fatigue testing device 1 comprises a fixing member 4 constituted by a lower jig 2 and an upper jig 3. The lower jig 2 and the upper jig 3 are fixed with a bolt 5, and a sheet or plate-shaped metal plate 6 is fixed in a cantilever state such that it is interposed between the lower jig 2 and the upper jig 3. The lower jig 2 has a fixing surface 2a to which the metal sheet or plate 6 is fixed, and the fixing surface 2a has a curved shape such that the space between the fixing surface 2a and the metal sheet or plate 6 increases with increasing distance from the location where the metal sheet or plate 6 is fixed to the fixing surface 2a. The upper jig 3 also has a fixing surface 3a to which the metal sheet or plate 6 is fixed, and the fixing surface 3a has a curved shape such that the space between the fixing surface 3a and the metal sheet or plate 6 increases with increasing distance from the location where the metal sheet or plate 6 is fixed to the fixing surface 3a.

Abstract: Provided is a martensitic stainless-steel sheet having a reduced anisotropy in workability and fatigue resistance which are attributable to oxide based inclusions. A martensitic stainless-steel sheet which has a steel composition that contains, in terms of mass %, 0.030 to 0.300% C, 0.20 to 2.50% Si, 0.15 to 4.00% Mn, 0.01 to 1.00% Ni, 11.00 to 15.00% Cr, 0.001 to 0.100% N, 0.0001 to 0.0350% Al, 0 to 0.50% V, 0 to 0.50% Nb, 0 to 0.50% Ti, 0 to 0.020% B, and a balance of Fe and unavoidable impurities, and that has a value of ?max, determined by the following equation (1), of 80.0 or greater, and in which oxide based inclusions are observed in the metallographic structure, the oxide based inclusions having a converted composition comprising up to 30 mass % or less Al2O3, 20 to 60 mass % SiO2, and 15 to 70 mass % MnO.

Abstract: A fatigue testing device 1 comprises a fixing member 4 constituted by a lower jig 2 and an upper jig 3. The lower jig 2 and the upper jig 3 are fixed with a bolt 5, and a sheet or plate-shaped metal plate 6 is fixed in a cantilever state such that it is interposed between the lower jig 2 and the upper jig 3. The lower jig 2 has a fixing surface 2a to which the metal sheet or plate 6 is fixed, and the fixing surface 2a has a curved shape such that the space between the fixing surface 2a and the metal sheet or plate 6 increases with increasing distance from the location where the metal sheet or plate 6 is fixed to the fixing surface 2a. The upper jig 3 also has a fixing surface 3a to which the metal sheet or plate 6 is fixed, and the fixing surface 3a has a curved shape such that the space between the fixing surface 3a and the metal sheet or plate 6 increases with increasing distance from the location where the metal sheet or plate 6 is fixed to the fixing surface 3a.

Abstract: [Problem] To provide a raw material steel sheet for providing a high strength nonmagnetic austenitic stainless steel material that has a high elastic limit stress and excellent toughness. [Solution to Problem] An austenitic stainless steel sheet containing 0.12% or less of C, from 0.30 to 3.00% of Si, from 2.0 to 9.0% of Mn, from 7.0 to 15.0% of Ni, from 11.0 to 20.0% of Cr, and 0.30% or less of N, and further containing at least one kind of 3.0% or less of Mo, 1.0% or less of V, 1.0% or less of Nb, 1.0% or less of Ti, and 0.010% or less of B, all in terms of percentage by mass, with the balance of Fe and unavoidable impurities, having a component composition having a Ni equivalent of 19.0 or more, having a value of d?1/2 of 0.40 or more, wherein d (?m) represents an average austenitic crystal grain diameter, and having a property that provides a magnetic permeability of 1.0100 or less after subjected to cold rolling with an equivalent strain of 0.50 or more.

Abstract: A Fe-Cr soft magnetic material has electric resistivity not less than 50 &mgr;&OHgr;·cm and a metallurgical structure occupied by a ferrite phase at a surface ratio of 95% or more. A number of fine precipitates of 1 &mgr;m or less in particle size is controlled at a ratio not more than 6×105/mm2. The Fe-Cr alloy has the composition (expressed in mass or weight %) of C up to 0.05%, N up to 0.05%, Si up to 3.0%, Mn up to 1.0%, P up to 0.04%, S up to 1.0%, 5.0-20.0% Cr, Al up to 4.0%, 0-3% Mo, 0-0.5% Ti and the balance being essentially Fe under the conditions of (1) and (2). The Fe-Cr soft magnetic material is useful as a core, a yoke or the like installed in various types of magnetic sensors such as electric power steering, fuel injection systems for vehicles and A.C. magnetic circuits of solenoid valves, due to production of high magnetic induction in a high-frequency low-magnetic field: 4.3×%Cr+19.1×%Si+15.1×%Al+2.5×%Mo≧40.

Abstract: A newly proposed Fe-Cr soft magnetic material has electric resistivity not less than 50 &mgr;&OHgr;·cm and a metallurgical structure occupied by a ferrite phase at a surface ratio of 95% or more. A number of fine precipitated of 1 &mgr;m or less in particle size is controlled at a ratio not more than 6×105/mm2. The Fe-Cr alloy has the composition of C up to 0.05%, N up to 0.05%, Si up to 3.0%, Mn up to 1.0%, P up to 0.04%, S up to 1.0%, 5.0-20.0% Cr, Al up to 4.0%, 0-3% Mo, 0-0.5% Ti and the balance being essentially Fe under the conditions of (1) and (2). The Fe-Cr soft magnetic material is useful as a core, a yoke or the like installed in various types of magnetic sensors such as electric power steering, fuel injection systems for vehicles and A.C magnetic circuits of solenoid valves, due to production of great magnetic induction in a high-frequency low-magnetic field.

Abstract: In a stepping motor, stator yokes have a plurality of comb-tooth-shaped magnetic poles 5b, 6b, 7b and 8b in such a manner that the comb-tooth-shaped magnetic poles are opposed to each other coaxially to a rotor portion made from a permanent magnet magnetized to have multiple magnetic poles, and an excitation coil is fitted on the external circumference of the stator yokes and the excitation coil and the stator yokes are surrounded by a frame yoke. Each of the yokes is formed of an Fe—Cr alloy having a predetermined ferrite single-phase structure so that occurrence of eddy currents in an alternating-current magnetic field is suppressed.

Abstract: Fe-Ni, Fe-Ni-Cr or Fe-Ni-Cr-Mo magnetic alloy material, the surface roughness of which is adjusted to Rz.gtoreq.0.5 or Ra.gtoreq.0.06, is disclosed. Parts made of this material has resistance to mutual adhesion or sticking when they are subjected to anealing treatment.