The present invention discloses a method for manufacturing a screwdriver head, the screwdriver head including a head portion for being inserted into a slot of a screw head and a basal body for supporting the head portion; the manufacturing method including: providing the screwdriver head made of a first metal material; preparing alloying coating; coating the alloying coating on the surface of the head portion of the screwdriver head; conducting laser surface alloying treatment on the surface of the head portion coated with the alloying coating to form an alloyed layer; and conducting low temperature tempering treatment on the screwdriver head after the laser surface alloying treatment. The present invention further discloses a screwdriver head, the surface of the position at which the head portion of the screwdriver head contacts with the slot of the screw head is provided with an alloyed layer formed through the laser surface alloying treatment. The screwdriver head manufactured by the manufacturing method of the present invention has high rigidity and high abrasive resistance in the head portion and high tenacity in other portions, thereby prolonging the service life.

The present invention discloses a method for manufacturing a screwdriver head, the screwdriver head including a head portion for being inserted into a slot of a screw head and a basal body for supporting the head portion; the manufacturing method including: providing the screwdriver head made of a first metal material; preparing alloying coating; coating the alloying coating on the surface of the head portion of the screwdriver head; conducting laser surface alloying treatment on the surface of the head portion coated with the alloying coating to form an alloyed layer; and conducting low temperature tempering treatment on the screwdriver head after the laser surface alloying treatment. The present invention further discloses a screwdriver head, the surface of the position at which the head portion of the screwdriver head contacts with the slot of the screw head is provided with an alloyed layer formed through the laser surface alloying treatment. The screwdriver head manufactured by the manufacturing method of the present invention has high rigidity and high abrasive resistance in the head portion and high tenacity in other portions, thereby prolonging the service life.

This steel sheet for hot stamping includes a base material, an Al—Si alloy plating layer in which the Al content is 75 mass % or more, the Si content is 3 mass % or more and the total of the Al content and the Si content is 95 mass % or more, an Al oxide coating having a thickness of 0 to 20 nm and a Ni plating layer in which the Ni content is more than 90 mass % in this order, the base material has a predetermined chemical composition, the Al—Si alloy plating layer has a thickness of 7 to 148 μm, and the Ni plating layer has a thickness of more than 200 nm and 2500 nm or less.

This high strength austenitic stainless steel having excellent resistance to hydrogen embrittlement includes, in terms of mass %, C: 0.2% or less, Si: 0.2% to 1.5%, Mn: 0.5% to 2.5%, P: 0.06% or less, S: 0.008% or less, Ni: 10.0% to 20.0%, Cr: 16.0% to 25.0%, Mo: 3.5% or less, Cu: 3.5% or less, N: 0.01% to 0.50%; and O: 0.015% or less, with the balance being Fe and unavoidable impurities, in which an average size of precipitates is 100 nm or less and an amount of the precipitates is 0.001% to 1.0% in terms of mass %.

A high-strength stainless steel rotor and a method for preparing the same, are provided. The high-strength stainless steel rotor, including the following element components by mass percentage: C: 0.03-0.050%, Cr: 14.90-15.80%, Ni: 5.00-5.70%, Cu: 2.20-2.80%, (Nb+Ta): 0.35-0.44%, Mo: 0.45-0.54%, V: 0.06-0.10%, Si: 0.20-0.60%, Mn: 0.40-0.80%, P≤0.010%, S≤0.010%, O≤0.003%, and the balance of iron and inevitable impurities.

Laser shock peening is applied to a harvester component for an agricultural wear application that for example may be any of the following components: a knifeback, a knifehead, a knifeback connecting strap, a straw chopper, a sickle section, stalk chopper, a bedknife, a sod cutter knife, a net wrap knife or a combine concave component. The laser shock peening may be selectively applied. For example, laser shock peening can be applied in regions of drive ends of harvester components, and/or in regions proximate fastener holes of such harvester components.

To provide a steel and a manufacturing method thereof that can contribute to achieving both high strength and hydrogen embrittlement resistance. The steel has a chemical composition represented by: C: 0.15% to 0.35%; Si: 0.8% to 2.5%; Mn: 0.8% to 2.5%; Al: 0.03% to 2.0%; N: 0.002% to 0.010%; P: 0.01% or less; S: 0.01% or less; O: 0.01% or less; B: 0.0001% to 0.005%; Nb: 0.0% to 0.05%; Ti: 0.0% to 0.2%; V 0.0% to 0.05%; Mo: 0.0% to 1.0%; Cr: 0.0% to 1.0%; Ni: 0.01% to 1.0%; Cu: 0.05% to 1.0%; at least one of Ca, Mg and REM: 0.0005% to 0.01%; and the balance: Fe and impurities, and has a martensite phase or/and a bainite phase in which ε-carbide is dispersedly precipitated.

The present invention suppresses leakage of combustion gas from a contact surface. A cylinder head (20) is attached to a cylinder block. The surface (26) of the side of the cylinder head (20) that is attached to the cylinder block includes a first region (AH1) and a second region (AH2) that has higher hardness than the first region (AH1).

A multi-opening oven assembly for simultaneously heating a plurality of blanks, for example aluminum blanks, before forming the heated blanks in a production line is provided. The oven assembly includes vertically aligned shelves to present a plurality of chambers for heating the blanks. A table including an entry side platform and an exit side platform moves vertically along the oven assembly. A rail system extends along the platforms and the shelves to convey the blanks in and out of the chambers. Once one set of heated blanks is removed from a first chamber, the table moves vertically to a second chamber and is ready to receive the next set of heated blanks. A continuous supply of heated blanks is provided for high throughput. The oven assembly is preferably disposed in a press adjacent a forming station of an existing production line and thus, no additional floor space is required.

Provided is a metal gasket including, expressed in mass %, C: 0.10% or less, Si: 1.0% or less, Mn: 2.0% or less, P: 0.04% or less (including 0%), S: 0.01% or less (including 0%), Ni: 25.0-60.0%, Cr: 10.0-20.0%, either Mo or W alone, or both Mo+W/2:0.05-5.0%, Al: more than 0.8% to 3.0% or less, Ti: 1.5-4.0%, Nb: 0.05-2.5%, V: 1.0% or less (including 0%), B: 0.001-0.015%, Mg: 0.0005-0.01%, S/Mg: 1.0 or less, N: 0.01% or less (including 0%), and O: 0.005%) or less (including 0%), with the remainder being Fe and unavoidable impurities. The metal gasket has a metal structure in which a precipitate γ′ phase having an average equivalent circle diameter of 25 nm or larger is not present within the austenite base.