C21D9/00

Hat member

A hat member 1 includes a top-plate portion 13, first ridges 113, and two side walls 11. The two side walls have a middle hardness Dc of 300 HV or higher. Each of the two side walls 11 includes a softened portion L and a strength-transition portion T adjacent to the softened portion L. The softened portion L has a hardness Dn lower than the middle hardness Dc by at least 8% (DcDn0.08Dc). The strength-transition portion T extends 0.5 mm or longer from the softened portion L toward the first end of the side wall. The strength-transition portion T has a hardness Dt that transitionally changes within the range of 8% to 1% lower than the middle hardness Dc (0.92DcDt0.99Dc). The hat member 1 further includes two second ridges 114 and two flanges 14.

STUD-WELDABLE REBAR

A stud-weldable rebar and a method for making the rebar are disclosed. The rebar has a steel body with a weld end and a diameter that is substantially uniform along a length of the body. A tip portion at the weld end includes a hardened zone and a base portion is formed of the remaining steel body. The hardened zone has a hardness that is about 1.5-3.0 times greater than a hardness of the base portion. Induction hardening is used to form the hardened zone.

Support fixture for heat treating sheets having complex shapes
10767241 · 2020-09-08 ·

A fixture is provided for holding sheets having complex shapes during heat treating. The fixture includes a base having a central opening and defining a peripheral foundation. A support structure extends inwardly and upwardly from the base and across the central opening. The support structure includes first axial and traverse openings extending there through. A sheet engagement structure is secured to the support structure and includes second axial openings extending there through. The sheet engagement structure has a peripheral section and at least one connecting leg extending between portions of the peripheral section. A sheet securing ring is removably secured to the sheet engagement structure for slidingly securing a sheet between the sheet securing ring and the sheet engagement structure. The central opening, first axial and traverse openings and second axial openings cooperating to create a uniform and accelerated flow of fluid through the fixture.

700MPa CLASS STEEL BAR HAVING EXCELLENT YIELD RATIO AND UNIFORM ELONGATION PROPERTY, AND METHOD FOR MANUFACTURING THE SAME

A steel bar having yield strength of 700 MPa class, excellent yield ratio, and excellent uniform elongation property is provided. The steel bar includes bainite and ferrite included in a center of the steel bar and bainite accounts for 20 to 80% by volume.

700MPa CLASS STEEL BAR HAVING EXCELLENT YIELD RATIO AND UNIFORM ELONGATION PROPERTY, AND METHOD FOR MANUFACTURING THE SAME

A steel bar having yield strength of 700 MPa class, excellent yield ratio, and excellent uniform elongation property is provided. The steel bar includes bainite and ferrite included in a center of the steel bar and bainite accounts for 20 to 80% by volume.

RAILWAY WHEEL
20200269632 · 2020-08-27 ·

To provide a railway wheel which is excellent in corrosion fatigue resistance. The railway wheel according to the present embodiment has a chemical composition consisting of: in mass %, C: 0.65 to 0.80%, Si: 0.10 to 1.0%, Mn: 0.10 to 1.0%, P: not more than 0.030%, S: not more than 0.030%, Cr: 0.05 to 0.20%, Sn: 0.005 to 0.50%, Al: 0.010 to 0.050%, N: 0.0020 to 0.015%, Cu: 0 to 0.20%, Ni: 0 to 0.20%, Mo: 0 to 0.20%, V: 0 to 0.20%, Nb: 0 to 0.030%, and Ti: 0 to 0.030%, with the balance being Fe and impurities. A plate portion has a matrix structure composed of pearlite.

REDUCTION AND REMOVAL OF PROCESS OXIDES ON STAINLESS STEEL
20200270719 · 2020-08-27 ·

Oxides formed during annealing of stainless steel strip are removed with abrasive brushes, in lieu of acid or molten salt based pickling. In some embodiments, the stainless steel strip is treated with a rare earth element or a related transition metal before annealing, and then brushed after annealing to remove any oxides. The selection of brushes can impart a finished appearance to conventionally polished stainless steel.

Method for producing turbine rotor and method for producing turbine

A method for producing a turbine rotor includes forming a rotor base material having a maximum outer diameter of 1000 mm or less from low-alloy steel including carbon, silicon, manganese, nickel, chromium, molybdenum, and vanadium; heating the rotor base material, by a quenching process, to a temperature range of 940 C. to 960 C.; performing oil quenching on the rotor base material, after the quenching process, in a temperature range of 250 C. to 500 C., at a cooling rate of at least 2.0 C./min; and tempering the rotor base material, after the quenching process, at a temperature of at least 630 C., and under a condition that a tempering parameter P is in the range of 19700 to 19900, wherein P is defined by the formula P=T (C+log(t)).

High Performance Iron-Based Alloys For Engine Valvetrain Applications And Methods of Making And Use Thereof

An iron-based alloy includes, in weight percent, carbon from about 1 to about 2 percent; manganese from about 0.1 to about 1 percent; silicon from about 0.1 to about 2.5 percent; chromium from about 11 to about 19 percent; nickel up to about 8 percent; vanadium from about 0.8 to about 5 percent; molybdenum from about 11 to about 19 percent; tungsten up to about 0.5 percent; niobium from about 1 to about 4 percent; cobalt up to about 5.5 percent; boron up to about 0.5 percent; nitrogen up to about 0.5 percent, copper up to about 1.5 percent, sulfur up to about 0.3 percent, phosphorus up to about 0.3 percent, up to about 5 percent total of tantalum, titanium, hafnium and zirconium; iron from about 50 to about 70 percent; and incidental impurities. The alloy is suitable for use in elevated temperature applications such as in valve seat inserts for combustion engines.

Piercer Plug and Method of Manufacturing the Same
20200263282 · 2020-08-20 ·

A piercer plug with increased recyclability is provided. A piercer plug (1) has a chemical composition of, in mass %: 0.15 to 0.30% C; 0.4 to 1.2% Si; 0.2 to 1.5% Mn; 0.1 to 2.0% Ni; 0 to 4.0% Mo and 0 to 4.0% W, where the total content of Mo and W is 1.0 to 6.0%; higher than 1.0% and not higher than 4.0% Cr; 0 to 0.2% B; 0 to 1.0% Nb; 0 to 1.0% V; 0 to 1.0% Ti; and balance Fe and impurities, the plug including a tip portion (2) and a trunk portion (3) made of the same material as the tip portion (2) and contiguous to the tip portion (2). The trunk portion (3) includes a cylindrical portion (5) having a hole used to mount a bar. The tip portion (2) is harder than the cylindrical portion (5).