Abstract: A method for manufacturing steel, by quenching and tempering a seamless pipe for use as a material of a hollow spring, where the seamless pipe including predetermined components is subjected to a heat treatment which is performed to satisfy quenching conditions (1) and tempering conditions (2), (1) quenching conditions: 26,000?(T1+273)×(log(t1)+20)?29,000 900° C.?T1?1,050° C., 10 seconds?t1?1,800 seconds,??formula (1) where T1 is a quenching temperature (° C.), and t1 is a holding time (seconds) in a temperature range of 900° C. or higher, and (2) tempering conditions: 13,000?(T2+273)×(log(t2)+20)?15,500 T2?550° C., and t2?3,600 seconds,??formula (2) where T2 is a tempering temperature (° C.), and t2 is a total time (seconds) from start of heating to completion of cooling.

Abstract: A method for manufacturing steel, by quenching and tempering a seamless pipe for use as a material of a hollow spring, where the seamless pipe including predetermined components is subjected to a heat treatment which is performed to satisfy quenching conditions (1) and tempering conditions (2), (1) quenching conditions: 26,000?(T1+273)×(log(t1)+20)?29,000??formula (1) 900° C.?T1?1,050° C., 10 seconds?t1?1,800 seconds, where T1 is a quenching temperature (° C.), and t1 is a holding time (seconds) in a temperature range of 900° C. or higher, and (2) tempering conditions: 13,000?(T2+273)×(log(t2)+20)?15,500??formula (2) T2?550° C., and t2?3,600 seconds, where T2 is a tempering temperature (° C.), and t2 is a total time (seconds) from start of heating to completion of cooling.

Abstract: A steel has a predetermined chemical composition with a balance being Fe and incidental impurities, wherein a sum of Cu content and Ni content is 0.15 mass % or more, and a crystal grain size after forming into a stabilizer shape and quenching is in a range of 7.5 to 10.5 in prior austenite crystal grain size number. Thus, a highly durable stabilizer steel that has a tensile strength of 1200 MPa or more and excellent normal-temperature and low-temperature toughness and is used in an environmentally friendly manufacturing process at lower cost can be realized.

Abstract: A steel, having a high corrosion resistance and low-temperature toughness, for a vehicle suspension spring part, the steel includes 0.21 to 0.35% by mass of C, more than 0.6% by mass but 1.5% by mass or less of Si, 1 to 3% by mass of Mn, 0.3 to 0.8% by mass of Cr, 0.005 to 0.080% by mass of sol. Al, 0.005 to 0.060% by mass of Ti, 0.005 to 0.060% by mass of Nb, not more than 150 ppm of N, not more than 0.035% by mass of P, not more than 0.035% by mass of S, 0.01 to 1.00% by mass of Cu, and 0.01 to 1.00% by mass of Ni, the balance being Fe and unavoidable impurities, with Ti+Nb?0.07% by mass, wherein crystal grains of the steel after hardening have a prior austenite grain size number of 7.5 to 10.5, and the steel having a tensile strength of not less than 1,300 MPa.

Abstract: A method for producing a leaf spring having a leaf portion and an eye portion formed at the leaf portion including: forming a gap between a leading end of the eye and a facing surface facing the leading end, and shot peening an inner surface of the eye via a reflection member, wherein, at a cross section perpendicular to an axial direction of the eye portion, the leading end of the eye faces the facing surface so a straight line does not cross the leading end of the eye, the straight line connecting an intersection point and a center point of a reflection member surface, the intersection point being the intersection of a line perpendicular to the facing surface extending through an endpoint of the leaf side of the leading end of the eye to the surface.

Abstract: A hollow stabilizer having an excellent fatigue property and higher strength compared to the conventional ones has a chemical composition containing 0.26% to 0.30% of C, 0.05% to 0.35% of Si, 0.5% to 1.0% of Mn, 0.05% to 1.0% of Cr, 0.005% to 0.05% of Ti, 0.0005% to 0.005% of B, and 0.0005% to 0.005% of Ca, wherein; Al, P, S, N, and O are limited to 0.08% or less, 0.05% or less, less than 0.0030%, 0.006% or less, and 0.004% or less, respectively, a remainder of the chemical composition consists of Fe and unavoidable impurities, a value of a product of the Mn content and the S content is 0.0025 or less, and a critical cooling rate Vc90 represented by a predetermined equation is 40° C./s or less; and wherein a metallic structure comprises a tempered martensite, a length of elongated MnS present at a center part in a thickness direction of the hollow stabilizer is 150 ?m or less, a HRC is from 40 to 50, a thickness to outer diameter ratio is 0.

Abstract: Disclosed is steel for a leaf spring with high fatigue strength containing, in mass percentage, C: 0.40 to 0.54%, Si: 0.40 to 0.90%, Mn: 0.40 to 1.20%, Cr: 0.70 to 1.50%, Ti: 0.070 to 0.150%, B: 0.0005 to 0.0050%, N: 0.0100% or less, and a remainder composed of Fe and impurity elements. Also disclosed is a high fatigue-strength leaf spring part obtained by forming the steel. The steel for a leaf spring is prepared to have a Ti content and a N content to satisfy a relation of Ti/N?10. Preferably, the leaf spring part is subjected to a shot peening treatment in a temperature range of the room temperature through 400° C. with a bending stress of 650 to 1900 MPa being applied to it.

Abstract: Steel, excellent in corrosion resistance and low-temperature toughness, for a vehicle suspension spring part, includes 0.15 to 0.35% by mass of C, more than 0.6% by mass but 1.5% by mass or less of Si, 1 to 3% by mass of Mn, 0.3 to 0.8% by mass of Cr, 0.005 to 0.080% by mass of sol. Al, 0.005 to 0.060% by mass of Ti, 0.005 to 0.060% by mass of Nb, not more than 150 ppm of N, not more than 0.035% by mass of P, not more than 0.035% by mass of S, 0.01 to 1.00% by mass of Cu, and 0.01 to 1.00% by mass of Ni, the balance consisting of Fe and unavoidable impurities, with Ti+Nb?0.07% by mass. The steel has a tensile strength of not less than 1,300 MPa.

Abstract: A method for producing a leaf spring having a leaf portion and an eye portion formed at the leaf portion including: forming a gap between a leading end of the eye and a facing surface facing the leading end, and shot peening an inner surface of the eye via a reflection member, wherein, at a cross section perpendicular to an axial direction of the eye portion, the leading end of the eye faces the facing surface so a straight line does not cross the leading end of the eye, the straight line connecting an intersection point and a center point of a reflection member surface, the intersection point being the intersection of a line perpendicular to the facing surface extending through an endpoint of the leaf side of the leading end of the eye to the surface.

Abstract: A stabilizer bar is intended for use in a vehicle, and a torsion part of the stabilizer bar is fixed to the vehicle body by a fixing member. A resin sheathing is provided integrally on an outer peripheral surface of the stabilizer bar. The fixing member is composed of the sheathing, a rubber bush disposed on the outer periphery of the sheathing, and a mounting fixture for mounting the rubber bush on the vehicle body side so as to cover the outer periphery of the rubber bush. The sheathing and the rubber bush are immovably assembled to each other. Thus, there may be provided a vehicle stabilizer, highly durable, easily mountable and replaceable, low-cost, and highly operable.

Abstract: Disclosed is steel for a leaf spring with high fatigue strength containing, in mass percentage, C: 0.40 to 0.54%, Si: 0.40 to 0.90%, Mn: 0.40 to 1.20%, Cr: 0.70 to 1.50%, Ti: 0.070 to 0.150%, B: 0.0005 to 0.0050%, N: 0.0100% or less, and a remainder composed of Fe and impurity elements. Also disclosed is a high fatigue-strength leaf spring part obtained by forming the steel. The steel for a leaf spring is prepared to have a Ti content and a N content to satisfy a relation of Ti/N?10. Preferably, the leaf spring part is subjected to a shot peening treatment in a temperature range of the room temperature through 400° C. with a bending stress of 650 to 1900 MPa being applied to it.

Abstract: A stabilizer bar is intended for use in a vehicle, and a torsion part of the stabilizer bar is fixed to the vehicle body by a fixing member. A resin sheathing is provided integrally on an outer peripheral surface of the stabilizer bar. The fixing member is composed of the sheathing, a rubber bush disposed on the outer periphery of the sheathing, and a mounting fixture for mounting the rubber bush on the vehicle body side so as to cover the outer periphery of the rubber bush. The sheathing and the rubber bush are immovably assembled to each other. Thus, there may be provided a vehicle stabilizer, highly durable, easily mountable and replaceable, low-cost, and highly operable.

Abstract: According to one embodiment, a high-strength stabilizer steel for vehicles having excellent corrosion resistance and low-temperature toughness, containing 0.07 to 0.20% C, more than 0.6% and 1.5% or less Si, 1 to 3% Mn, 0.1 to 1.0% Cr, 0.005 to 0.080% sAl, 0.005 to 0.060% Ti, 0.005 to 0.060% Nb, 0.070% or less Ti+Nb, 150 ppm or less N, 0.035% or less P, 0.035% or less S, 0.01 to 1.00% Cu, 0.01 to 1.00% Ni, the remainder being Fe, and unavoidable impurities, wherein a structure before molding a stabilizer is any one of a bainite, a martensite, and a mixed structure of bainite/martensite and an original austenitic crystal grain size number after a heat treatment of the stabilizer is Gh 9 or more.

Abstract: According to one embodiment, a high-strength stabilizer steel for vehicles having excellent corrosion resistance and low-temperature toughness, containing 0.07 to 0.20% C, more than 0.6% and 1.5% or less Si, 1 to 3% Mn, 0.1 to 1.0% Cr, 0.005 to 0.080% sAl, 0.005 to 0.060% Ti, 0.005 to 0.060% Nb, 0.070% or less Ti+Nb, 150 ppm or less N, 0.035% or less P, 0.035% or less S, 0.01 to 1.00% Cu, 0.01 to 1.00% Ni, the remainder being Fe, and unavoidable impurities, wherein a structure before molding a stabilizer is any one of a bainite, a martensite, and a mixed structure of bainite/martensite and an original austenitic crystal grain size number after a heat treatment of the stabilizer is Gh 9 or more.

Abstract: A stabilizer bar is intended for use in a vehicle, and a torsion part of the stabilizer bar is fixed to the vehicle body by a fixing member. A resin sheathing is provided integrally on an outer peripheral surface of the stabilizer bar. The fixing member is composed of the sheathing, a rubber bush disposed on the outer periphery of the sheathing, and a mounting fixture for mounting the rubber bush on the vehicle body side so as to cover the outer periphery of the rubber bush. The sheathing and the rubber bush are immovably assembled to each other. Thus, there may be provided a vehicle stabilizer, highly durable, easily mountable and replaceable, low-cost, and highly operable.

Abstract: Disclosed is an improved laminated metallic belt consisting of at least two layers of an endless metallic band for use in a torque transmission device, which can transmit torque between two pulleys having variable effective radii, in combination with a plurality of metallic blocks which have surfaces contacting the innermost layer of the laminated metallic belt and are arranged along the laminated metallic belt. The metallic belt according to the present invention may be made of precipitation hardening martensitic stainless steel or maraging steel which have favorable properties as to toughness, mechanical strength and the adaptability for welding required for making an endless laminated metallic belt, but lack the surface hardness to ensure relatively favorable durability. The durability of the steel is improved according to the present invention by a nitride layer and/or an electroless nickel plating layer formed on the side edges of the endless metallic band.