A soft magnetic alloy powder which is a soft magnetic alloy powder having a low coercivity, and with which it is possible to obtain a green compact magnetic core having a high magnetic permeability. A soft magnetic alloy powder including a composition formula (Fe(1−(α+β))X1 αX2 β) (1−(a+b+c+d+e+f)) MaBbPcSidCeSf. XI is one or more elements selected from the group consisting of Co and Ni, X2 is one or more elements selected from the group consisting or Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements, and M is one or more elements selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V. The amount of each component contained is within a specified range. The amorphous rate X (%) is at least 85%.

Provided is a low thermal expansion alloy wherein martensitic transformation does not occur even at −120° C. This low thermal expansion alloy contains, in mass %, 1.50-5.00% of Co, while containing Ni in such an amount that if [Ni] (mass %) is the content of Ni and [Co] (mass %) is the content of Co, [Co]≥−4×[Ni]+136 and [Co]≤−4×[Ni]+139 are satisfied, with the balance being made up of Fe and unavoidable impurities. This low thermal expansion alloy has an average thermal expansion coefficient of 0.5×10.sup.−6/° C. or less for the range of 0-30° C., while having a martensitic transformation temperature of −120° C. or less.

A soft magnetic alloy comprising 2 wt %≤Co≤30 wt %, 0.3 wt %≤V≤5.0 wt % and iron is provided. The soft magnetic alloy has a area proportion of a {111}<uvw> texture of no more than 13%, preferably no more than 6%, including grains with a tilt of up to +/−10°, or preferably of up to +/−15°, when compared to the nominal crystal orientation.

Provided is an electric-resistance-welded steel pipe or tube for hollow stabilizer excellent in corrosion fatigue resistance having: a chemical composition containing, in mass %, C: 0.15% or more and less than 0.20%, Si: 0.1% or more and 1.0% or less, Mn: 0.1% or more and 2.0% or less, P: 0.1% or less, S: 0.01% or less, Al: 0.01% or more and 0.10% or less, Ti: more than 0.05% and 0.1% or less, B: 0.0005% or more and 0.005% or less, Ca: 0.0001% or more and 0.0050% or less, and N: 0.0050% or less, with the balance being Fe and inevitable impurities; and a microstructure containing TiS and MnS particles which each have a particle size of 10 μm or more, the TiS and MnS particles having a cleanliness of 0% or more and 0.1% or less as measured by a point counting method according to JIS G 0555.

Described is a hot-rolled steel strip product including a composition consisting of, in terms of weight percentages, 0.14% to 0.35% C, 0% to 0.5% Si, 0.05% to 0.40% Mn, 0.1% or less Al, 0.1% to 0.4% Cu, 0.2% to 0.9% Ni, 0.2% to 0.9% Cr, 0.2% or less Mo, 0.005% or less Nb, 0.035% or less Ti, 0.05% or less V, 0.0005% to 0.0050% B, 0.025% or less P, 0.008% or less S, 0.01% or less N, 0.01% or less Ca, and the remainder being Fe and inevitable impurities, wherein the steel product has a Brinell hardness in the range of 420 to 580 HBW.

Provided is a steel sheet having a predetermined chemical composition and structure wherein (Fe, Mn).sub.2 B precipitates having a circle equivalent diameter of 50 to 300 nm are present in a number density of 1/500 μm.sup.2 or more in a surface layer region down to a depth of 100 μm from the surface in the sheet thickness direction. Further, provided is a method for producing a steel sheet comprising continuously casting a molten steel having a predetermined chemical composition to form a steel slab, wherein the continuously casting includes introducing more than 10 ppm and less than 100 ppm of oxygen into the surface layer of the steel slab, hot rolling including finish rolling the steel slab, wherein a completion temperature of the finish rolling is 650 to 950° C., coiling the obtained hot rolled steel sheet at a coiling temperature of 400 to 700° C., and cold rolling the hot rolled steel sheet, then annealing it.

A high strength steel sheet according to the present invention contains a predetermined chemical composition, a metallographic structure includes, by an area ratio, ferrite: 20% to 70%, residual austenite: 5% to 40%, fresh martensite: 0% to 30%, tempered martensite and bainite: 20% to 75% in total, and pearlite and cementite: 0% to 10% in total, in a range of a ⅛ thickness to a ⅜ thickness from a surface, a number proportion of residual austenite having an aspect ratio of 2.0 or more with respect to the number of all residual austenite is 50% or more, at a sheet thickness ¼ position of a cross section parallel to a rolling direction and perpendicular to the surface, a standard deviation of area ratios of ferrite measured at 10 points every 50 mm along a width direction is less than 10%, and a tensile strength is 780 MPa or more.

A steel product includes the following chemical composition in wt. %: C: 0.01 to <0.3, Mn: 4 to <10, Al: 0.003 to 2.9, Mo: 0.01 to 0.8, Si: 0.02 to 0.8, Ni: 0.005 to 3, P: <0.04, S: <0.02, N: <0.02, with the remainder being iron including unavoidable steel-associated elements, wherein an alloy composition satisfies the equation 6<1.5 Mn+Ni<8; or the equation 0.11<C+Al<3, or an alloy composition contains, in addition to Ni, at least one or more of the elements, in wt. %, B: 0.0005 to 0.014; V: 0.006 to 0.1; Nb: 0.003 to 0.1; Co: 0.003 to 3; W: 0.03 to 2 or Zr: 0.03 to 1. The steel product has a microstructure of 2 to 90 vol. % austenite, less than 40 vol. % ferrite and/or bainite, with the remainder being martensite.

Disclosed is an AlNiCo-based hard magnetic particle containing Al, Ni, Co, Cu, Ti, and the balance of Fe. The AlNiCo-based hard magnetic particle contains Co in an amount of 10 to 17 wt %, has a coercive force of 250-450 Oe, and has a residual magnetization/coercive force rate of 0.06 or more. The AlNiCo-based hard magnetic particle according to the present invention can advantageously guarantee magnetic properties suitable for being detected by a magnetic reluctance device due to a low content of Co.

Provided is an alloy powder capable of obtaining a magnetic member therefrom in which the frequency FR is extremely high. The powder for the magnetic member is composed of a plurality of flaky particles. These flaky particles are composed of an Fe-based alloy including: 6.5% by mass or more and 32.0% by mass or less of Ni; 6.0% by mass or more and 14.0% by mass or less of Al; 0% by mass or more and 17.0% by mass or less of Co; and 0% by mass or more and 7.0% by mass or less of Cu; the balance being Fe and unavoidable impurities. The average thickness Tav of this powder is 3.0 μm or less. The saturation magnetization Ms of this powder is 0.9 T or more. The coercive force iHc of this powder is 16 kA/m or more. This Fe-based alloy has a structure resulting from spinodal decomposition.