Shinko Kosen Kogyo Kabushiki Kaisha

Kabushiki Kaisha Kobe Seiko Sho

Shinko Kosen Kogyo Kabushiki

Yukio Yamaoka

Masaru Kodama

Kishio Tamai

Nobuhiko Ibaraki

Yoshiro Yamada

Masato Kaiso

Yasunobu Kawaguchi

Hiroyuki Takahashi

Tadayoshi Fujiwara

Yasuhiro Oki

Hirofumi Ueki

Masao Yamada

Keiji Hattori

Suchun Fang

Tetsuro Noma

Takashi Taniguchi

Kazuichi Hamada

Hiroshi Masutani

Toshiki Suwa

A high strength steel strand for PC of a wire material having a pearlite structure and containing 0.80 to 1.30% of C, 0.60 to 2.50% of Si and 0.30 to 1.50% of Mn, remainder being Fe and unavoidable impurities, wherein a cementite portion of the wire material comprises a mixed structure of fibrous cementite and granular cementite, the volumetric proportion of the granular cementite to the total cementite is 10 to 40%, the particle diameter of the granular cementite is 40 to 300.ANG., and the strand has a tensile strength of 235 kgf/mm.sup.2 or higher and an elongation of 3.5% or greater.

High strength steel strand for prestressed concrete and method for

Disclosed is a stainless steel wire made of a two-phase stainless steel having austenite and ferrite, which is used as a PC tension member and wire rope both for dynamic and static use. The stainless steel wire contains 0.01-0.10 wt % of C, 0.1-1.0 wt % of Si, 0.30-1.50% of Mn, 0.010-0.040 wt % of P, 0.001-0.030 wt % of S, 18.0-30.0 wt % of Cr, 3.0-8.0 wt % of Ni, 0.1-3.0 wt % of Mo, and 0.10-0.45 wt % of N, the balance being essentially Fe and inevitable impurities, wherein the volume ratio of the ferrite to the sum of the austenite and the ferrite is specified to be in the range from 20.0 to 80.0%. Upon drawing, the drawing draft is in the range from 40 to 97%, the mean slenderness ratio (M.sub.R value) is in the range from 4 to 20, and the aging temperature is in the range from 150.degree. to 750.degree. C. This stainless steel wire product provides a tension member suitable for tension members, hanging members and cables, that is high in tensile strength, elongation, fatigue strength, reduction of area, and torsion value, and low in relaxation value, and high in corrosion resistance. Moreover, provided is a stainless steel wire rope having corrosion resistance higher than wire ropes made of SUS304 and SUS316 and a fatigue strength higher than high carbon steel wire ropes, which is applicable for either dynamic or static use.

Stainless steel wire product

A two-phase stainless steel wire rope having a high fatigue resistance and a high corrosion resistance, containing two-phase stainless steel wires of 0.03 to 0.1% by weight of C, 0.33 to 1.0% by weight of Si, 0.65 to 1.5% by weight of Mn, 0.019 to 0.04% by weight P, 0.004 to 0.03% by weight of S, 18.21 to 30% by weight of Cr, 3.10 to 8.0% by weight of Ni, 0.1 to 3.0% by weight of Mo, with the balance being Fe, and 30.0 to 80.0% by volume of ferrite, which wire rope has a means slenderness ratio, M.sub.R, of 4 to 20 by wire drawing.

Two-phase stainless steel wire rope having high fatigue resistance and

A steel wire is coated with a ternary alloy of iron, zinc and aluminum on an outermost surface thereof. The ternary alloy contains 10 to 30 weight percent of aluminum. The steel wire is primarily used as material for springs. An Fe--Zn--Al ternary alloy coated steel wire production method includes immersing a steel wire in a zinc molten bath to plate the steel wire with zinc; immersing the zinc-plated steel wire in a zinc-aluminum molten bath to form a ternary alloy of iron, zinc, and aluminum on a surface of the steel wire; and removing an unsolidified zinc-aluminum layer depositing on an outer surface of the steel wire while being taken out of the zinc-aluminum molten bath to expose the ternary alloy on an outermost surface of the steel wire.

Steel wire coated with Fe-Zn-Al alloys and method for producing the same

Facilitating the distinction among different spring steel products and at the same time improving their surface appearance and corrosion resistance by plating the surface of said different spring steel products before spring-forming with either alternate layers of Cu and Zn or alternate layers of Ni, Cu and Zn, the amount of Cu and Zn differing for steel products differing in size and/or material, to obtain color-developable spring steel products, drawing and taken coil spring-forming the resulting plated spring steel products, and low temperature annealing said resulting plated spring steel products to develop their colors, the colors being different for spring steel products differing in size and/or material, whereby mixing and erroneous assembly of spring steel products differing in size and/or material is prevented.

Method for facilitating distinction between different steel products

Wire rods containing an adequate quantity of C within the range from 0.70 to 1.00%, Si from 0.5 to 3.0%, Mn from 0.30 to 2.0%, Cr from 0.10 to 0.5%, Al from 0.030 to 0.10% and N from 0.004 to 0.015% and unavoidable impurities, and with Fe for all the rest are subjected to re-heat patenting to increase the tensile strength to 135 kgf/mm.sup.2 or higher, then are drawn by adequately selecting the conditions, number of times of drawing in the range from 7 to 16 times, drawings speed from 50 to 550 m/minute, extent of drawing form 70-90, and water cooling immediately after each drawing to manufacture steel wires of high strength and high toughness. The wires are used as PC wires, steel wires for skewed bridge cables, steel stranded wires, spring wires, main cable wires for extra-long suspension bridge large diameter wires for core of aluminum cables steel reinforced (transmission cable), and as galvanized steel wires for such applications.

High strength and high toughness steel bar, rod and wire and the process

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Sakai, Japan

Yukio Yamaoka