A method and apparatus are present for manufacturing a part. The part is comprised of a metal alloy and is positioned to form a positioned part. An electromagnetic field is generated that heats the positioned part. A surface of the positioned part is exposed to an inert gas, while the electromagnetic field is generated to create an inverse thermal gradient between an exterior of the positioned part and an interior section of the positioned part to form a heat treated part.

Provided is an austenitic heat resistant alloy having high creep strength and high toughness even in a high temperature environment. This austenitic heat resistant alloy has a chemical composition consisting of: in mass %, C: 0.03 to less than 0.25%, Si: 0.01 to 2.0%, Mn: not more than 2.0%, Cr: 10 to less than 30%, Ni: more than 25 to 45%, Al: more than 2.5 to less than 4.5%, Nb: 0.2 to 3.5%, N: not more than 0.025%, with the balance being Fe and impurities, wherein P and S in the impurities are respectively, P: not more than 0.04% and S: not more than 0.01%. In the structure, a total volume ratio of precipitates having a circle equivalent diameter of not less than 6 m is not more than 5%.

Nickel-iron-cobalt based alloys are disclosed having sufficient castability for centrifugal casting essentially free from casting defects, cracking, and microstructure variability, and coefficients of thermal expansion up to about 910.sup.6/ C. for about 100-400 C. and increasing from about 400-500 C. to up to about 1010.sup.6/ C., or up to about 610.sup.6/ C. between about 100-300 C. and increasing from about 300-500 C. to up to about 1010.sup.6/ C. Articles are disclosed including unitary cast structures free of internal welds, brazing, and bolting, essentially annular conformations, diameters of at least about 500 mm, cross-sectional wall areas of at least about 2,000 mm.sup.2, and compositions including nickel-iron-cobalt based alloys. Methods for forming the articles are disclosed including rotating centrifugal molds with the compositions in molten states, forming the articles in near net shape.

Nickel-iron-cobalt based alloys are disclosed having sufficient castability for centrifugal casting essentially free from casting defects, cracking, and microstructure variability, and coefficients of thermal expansion up to about 910.sup.6/ C. for about 100-400 C. and increasing from about 400-500 C. to up to about 1010.sup.6/ C., or up to about 610.sup.6/ C. between about 100-300 C. and increasing from about 300-500 C. to up to about 1010.sup.6/ C. Articles are disclosed including unitary cast structures free of internal welds, brazing, and bolting, essentially annular conformations, diameters of at least about 500 mm, cross-sectional wall areas of at least about 2,000 mm.sup.2, and compositions including nickel-iron-cobalt based alloys. Methods for forming the articles are disclosed including rotating centrifugal molds with the compositions in molten states, forming the articles in near net shape.

Provided are a part for vehicle having high strength and excellent durability, and a manufacturing method therefor. The part for vehicle comprises, by a weight ratio, a composition comprising 0.20-0.50% of C, 0.5% or less of Si, 1.0-2.0% of Mn, 0.01-0.1% of Al, 0.010% or less of P, 0.003% or less of S, 0.01-0.1% of Ti, 0.05-0.5% of Cr, 0.05-0.3% of Mo, 0.01% or less of N, and the remainder being Fe and other inevitable impurities, and the part for vehicle can have, by an area ratio, a microstructure comprising 90% or more of tempered martensite, 4% or less of retained austenite, and the remainder being one type or both of two types selected from among the ferrite and bainite structures.

The invention relates hot work tool steel. The steel comprises the following main components (in wt. %):

TABLE-US-00001 C 0.27-0.38 Si 0.10-0.35 Mn 0.2-0.7 Cr 4.5-5.5 Mo 2.05-2.90 V 0.4-0.6 N 0.01-0.12 H 0.0004 S 0.0015 balance optional elements, iron and impurities.

A hollow screw and related process of making is provided, wherein the hollow screw is formed from a generally circular corrosion resistant stainless steel disk cut from flat roll stock. The hollow screw includes a head and an elongated and hollow shaft having a wall thickness between about 0.2 to about 0.7 millimeters extending therefrom and defining a shank portion and a threaded portion having a plurality of threads thereon with a rotational drive mechanism configured to facilitate tightening via the threads. The process involves annealing to soften the stamped hollow screw, followed by thread rolling, and then age hardening the hollow screw. As such, the resultant hollow screw is relatively lightweight, about 50% the mass of a solid core screw made from the same material, with a sufficient thread strength to meet most aerospace applications and contributes to important aircraft fuel economy.

A hollow screw and related process of making is provided, wherein the hollow screw is formed from a generally circular corrosion resistant stainless steel disk cut from flat roll stock. The hollow screw includes a head and an elongated and hollow shaft having a wall thickness between about 0.2 to about 0.7 millimeters extending therefrom and defining a shank portion and a threaded portion having a plurality of threads thereon with a rotational drive mechanism configured to facilitate tightening via the threads. The process involves annealing to soften the stamped hollow screw, followed by thread rolling, and then age hardening the hollow screw. As such, the resultant hollow screw is relatively lightweight, about 50% the mass of a solid core screw made from the same material, with a sufficient thread strength to meet most aerospace applications and contributes to important aircraft fuel economy.

Provided are a high-speed tool steel having excellent hot workability, and excellent damage resistance when made into various tools; a material for tools, and a method for producing the same. The high-speed tool steel contains, in mass %, 0.9-1.2% of C, 0.1-1.0% of Si, 1.0% or less of Mn, 3.0-5.0% of Cr, 2.1-3.5% of W, 9.0-10.0% of Mo, 0.9-1.2% of V, 5.0-10.0% of Co, 0.020% or less of N, and the remainder being Fe and impurities, wherein an M value calculated by a formula satisfies 1.5M value1.5. Formula: M value=9.500+9.334[% C]0.275[% Si]0.566[% W]0.404[% Mo]+3.980[% V]+0.166[% Co], where the characters in brackets [ ] indicate the contained amounts (mass %) of the respective elements. The present invention also pertains to: a material for tools, which is obtained by using the high-speed tool steel; and a method for producing the material for tools.

A precipitation hardening type soft magnetic ferritic stainless steel having an excellent machinability contains, in % by mass, C: 0.1% or less (excluding 0%), Si: 0.01 to 2.5%, Mn: 0.5% or less (excluding 0%), S: 0.1% or less (excluding 0%), Cr: 12.0 to 19.0%, Ni: 1.0 to 4.0%, Al: 0.5 to 3.0%, and at least one of Ti: 0.05 to less than 0.5% and Zr: 0.05 to less than 0.3%, as well as Bi: 0.02 to 0.5%, in which a remainder includes inevitable impurities and substantially is made of Fe, and the stainless steel has a structure substantially in a ferrite phase after solution annealing and aging, and a hardness of 300 Hv or higher after aging. The precipitation hardening type soft magnetic ferritic stainless steel is excellent in soft magnetic properties, age-hardenability, and corrosion resistance, as well as machinability.