Carbon steel for a rack bar contains 0.50 to 0.55% by weight of carbon (C), 0.15 to 0.35% by weight of silicon (Si), 0.75 to 0.95% by weight of manganese (Mn), 0.025% by weight or less of phosphorus (P), 0.025% by weight or less of sulfur (S), 0.65 to 0.85% by weight of chrome (Cr), 0.20% by weight or less of molybdenum (Mo), 0.001 to 0.02% by weight of aluminum (Al), 5 to 50 ppm of boron (B), and iron (Fe) as a remainder and unavoidable impurities. A method for manufacturing the rack bar includes quenching, tempering, and drawing the carbon steel and warm forging the drawn carbon steel.

There is provided a metal-coated Al bonding wire which can provide a sufficient bonding reliability of bonded parts of the bonding wire under a high temperature state where a semiconductor device using the metal-coated Al bonding wire is operated. The bonding wire includes a core wire of Al or Al alloy, and a coating layer of Ag, Au or an alloy containing them formed on the outer periphery of the core wire, and the bonding wire is characterized in that when measuring crystal orientations on a cross-section of the core wire in a direction perpendicular to a wire axis of the bonding wire, a crystal orientation <111> angled at 15 degrees or less to a wire longitudinal direction has a proportion of 30 to 90% among crystal orientations in the wire longitudinal direction. Preferably, the surface roughness of the wire is 2 μm or less in terms of Rz.

A probe pin material including a Ag—Pd—Cu-based alloy essentially including Ag, Pd and Cu, B as a first additive element, and at least any element of Zn, Bi and Sn, as a second additive element. A concentration of the first additive element is 0.1 mass % or more and 1.5 mass % or less, and a concentration of the second additive element is 0.1 mass % or more and 1.0 mass % or less. A Ag concentration, a Pd concentration and a Cu concentration in the Ag—Pd—Cu-based alloy are required as follows: a Ag concentration (S.sub.Ag), a Pd concentration (S.sub.Pd) and a Cu concentration (S.sub.Cu) converted as given that a Ag—Pd—Cu ternary alloy is formed from only such three elements all fall within a predetermined range in a Ag—Pd—Cu ternary system phase diagram. The probe pin material is excellent in resistance value and hardness/wear resistance, and also is enhanced in bending resistance.

Provided is a dehydrogenation method capable of efficiently reducing hydrogen content in steel for thick or complexly-shaped steel materials and steel products in general. In a dehydrogenation method for a steel material, in a series of steel material production process including: a process of supplying a steel raw material; a process of subjecting the steel raw material to hot working; a process of inspecting a steel material obtained from the steel raw material; and a process of shipping the steel material, at least one of the steel raw material and the steel material at any stage from the supply process to the shipment process is subjected to, at least once, a sound wave irradiation treatment so that a sound pressure level at a surface of the at least one of the steel raw material and the steel material will be 30 dB or more.

Provided are a steel wire having excellent straightness quality and a method of manufacturing the steel wire, wherein the steel wire includes a wire, after undergoing a drawing operation, undergoing a heating operation of performing heating in a state in which tension is applied, and undergoing a cooling operation, wherein, when winding the wire around a winding portion having a diameter greater than a diameter of the wire for a preset period of time and then measuring straightness of the wire of 400 mm, the straightness of the wire is less than or equal to 30 mm, and the method includes a wire preparation operation, a heating operation, a cooling operation, and a straightness measurement operation.

The present disclosure relates to a duplex stainless steel comprising in weight % (wt %): C less than 0.03; Si less than 0.60; Mn 0.40 to 2.00; P less than 0.04; S less than or equal to 0.01; Cr more than 30.00 to 33.00; Ni 6.00 to 10.00; Mo 1.30 to 2.90; N 0.15 to 0.28; Cu 0.60 to 2.20; Al less than 0.05; balance Fe and unavoidable impurities. The present disclosure also relates to a component or a construction material comprising the duplex stainless steel. Additionally, the present disclosure also relates to a process for manufacturing a component comprising said duplex stainless steel.

The invention relates to a steel wire suitable for making a spring or medical wire products which remarkably improve the performance of conventional stainless steel wire. The steel comprises (in wt. %): C: 0.02 to 0.15, Si: 0.1 to 0.9, Mn: 0.8 to 1.6, Cr 16 to 20, Ni: 7.5 to 10.5, Mo: ≤3, Al: 0.5 to 2.5, Ti: ≤0.15, N: ≤0.05, optional elements, and impurities, balance Fe, wherein the total amount of Cr and Ni is 25 to 27 wt. %, and wherein the steel has a microstructure including, in volume % (vol. %), martensite: 40 to 90, austenite: 10 to 60, and delta ferrite: ≤5.

An embodiment of the present invention provides a wire rod and a steel wire which are for springs and have excellent corrosion fatigue resistance properties, and a method for producing same, the wire rod and steel wire containing, in wt %, 0.40-0.70% of C, 1.20-2.30% of Si, 0.20-0.80% of Mn, 0.20-0.80% of Cr, 0.015% or less of P, 0.015% or less of S, and 0.010% or less of N, with the remainder comprising Fe and other unavoidable impurities, along with at least one among 0.01-0.20% of V and 0.01-0.10% of Nb, wherein the V and Nb satisfy relational expression 1 below, the average grain size of prior austenite is no greater than 20 μm, and the surface decarburization depth is no greater than 0.1 mm. [Relational expression 1] [V]+[Nb]≥0.08 (where the V and Nb contents are in wt %).

A case hardening steel suitable as raw material for producing a mechanical structural part having high rotating bending fatigue strength and pitting fatigue strength at relatively low cost and a method of producing the case hardening steel are provided. A case hardening steel comprises a chemical composition containing, in mass %, C, Si, Mn, P, S, Cr, Mo, Al, N, and O in a predetermined relationship, with a balance being Fe and inevitable impurities, wherein √I≤80 (where I denotes an area (μm.sup.2) of an oxide-based inclusion located in a fish eye central portion at a fracture surface after subjecting the case hardening steel to carburizing-quenching and tempering and then performing a rotating bending fatigue test).

An α+β type titanium alloy wire contains, in mass %, Al: 4.50 to 6.75%, Si: 0 to 0.50%, C: 0.080% or less, N: 0.050% or less, H: 0.016% or less, O: 0.25% or less, Mo: 0 to 5.5%, V: 0 to 4.50%, Nb: 0 to 3.0%, Fe: 0 to 2.10%, Cr: 0 to less than 0.25%, Ni: 0 to less than 0.15%, Mn: 0 to less than 0.25%, and the balance being Ti and impurities, the contents of Al, Mo, V, Nb, Fe, Cr, Ni, and Mn satisfying an equation, in which an average aspect ratio of an α crystal grain is 1.0 to 3.0, a maximum crystal grain diameter of the α crystal grain is 30.0 μm or less, an average crystal grain diameter of the α crystal grain is 1.0 to 15.0 μm.