Disclosed are a Nb microalloyed high strength high hole expansion steel and a production method therefor. The chemical ingredients of the steel in percentages by weight are as follows: 0.01-0.05% of C, 0.2-0.6% of Si, 0.8-1.5% of Mn, ≤0.02% of P, ≤0.005% of S, ≤0.008% of N, <0.001% of Als, ≤0.0050% of Ca, 0.01-0.08% of Nb, and optionally one or both of 0.1-0.6% of Cu and 0.005-0.04% of Sn, wherein Mn/S>250, total oxygen [O].sub.T is 0.007-0.020%, and the balance is Fe and inevitable impurities. In the present invention, microalloy elements such as Nb are selectively added, and the basicity of slag, the type and melting point of the inclusion in steel, the content of free oxygen in molten steel, and the content of acid-soluble aluminum Als during the smelting process are controlled, and then, a strip is cast by means of twin-roll thin strip continuous casting, and the strip directly enters a lower closed chamber in a non-oxidizing atmosphere and enters an online rolling mill for hot rolling in closed conditions, and after rolling, the strip steel is cooled by air atomization cooling, and finally, the produced steel coil can be used directly as a hot rolled plate or can be used after acid pickling and leveling.

Provided is a method for producing a Ni- or Ti-based alloy product, the method capable of locally increasing the cooling rate and effectively cooling. The method includes the steps: preliminarily processing a hot working material of a Ni- or Ti-based alloy after hot working into a predetermined shape; heating and holding the material at a solution treatment temperature to obtain a material held in a heated state; and cooling the material held in a heated state to obtain a solution-treated material. The cooling step includes placing a flow path-forming member having a space for forming a flow path for a fluid on a surface of the material held in a heated state to form a fluid flow path defined by the surface of the material held in a heated state and an inner surface of the space of the flow path-forming member; and allowing a fluid to flow in the fluid flow path so that the fluid in the flow path locally cools a part of the surface of the material held in a heated state.

Disclosed are a continuous heat treatment device and method for a sintered Nd—Fe—B magnet workpiece. The device comprises a first heat treatment chamber, a first cooling chamber, a second heat treatment chamber, and a second cooling chamber continuously disposed in sequence, as well as a transfer system disposed among the chambers to transfer the alloy workpiece or the metal workpiece; both the first cooling chamber and the second cooling chamber adopt a air cooling system, wherein a cooling air temperature of the first cooling chamber is 25° C. or above and differs from a heat treatment temperature of the first heat treatment chamber by at least 450° C.; a cooling air temperature of the second cooling chamber is 25° C. or above and differs from a heat treatment temperature of the second heat treatment chamber by at least 300° C. The continuous heat treatment device and method can improve the cooling rate and production efficiency and improve the properties and consistency of the products.

Disclosed are a continuous heat treatment device and method for a sintered Nd—Fe—B magnet workpiece. The device comprises a first heat treatment chamber, a first cooling chamber, a second heat treatment chamber, and a second cooling chamber continuously disposed in sequence, as well as a transfer system disposed among the chambers to transfer the alloy workpiece or the metal workpiece; both the first cooling chamber and the second cooling chamber adopt a air cooling system, wherein a cooling air temperature of the first cooling chamber is 25° C. or above and differs from a heat treatment temperature of the first heat treatment chamber by at least 450° C.; a cooling air temperature of the second cooling chamber is 25° C. or above and differs from a heat treatment temperature of the second heat treatment chamber by at least 300° C. The continuous heat treatment device and method can improve the cooling rate and production efficiency and improve the properties and consistency of the products.

The invention relates to a method for producing a sintered component comprising the steps: providing a metallic powder; filling the powder into a powder press; pressing the powder to form a green compact; removing the green compact from the powder press; sintering the green compact into a sintered component with pores; optional redensification of the sintered component; hardening of the sintered component, wherein the pores of the sintered component, prior to hardening at least in that region of the surface of the sintered component which is subjected to a hardening, are at least partially filled with a filling agent.

The present description concerns a gas cooling cell, comprising: a chamber; at least one opening in the chamber, of access to a treatment space internal to the chamber; at least one door for closing the opening; and a system (4), internal to the chamber, comprising at least one wall (42) mobile between a first position where this wall forms a screen between the opening and the treatment space, and a second position where said wall clears the access to the treatment space from the opening.

The present description concerns a gas cooling cell, comprising: a chamber; at least one opening in the chamber, of access to a treatment space internal to the chamber; at least one door for closing the opening; and a system (4), internal to the chamber, comprising at least one wall (42) mobile between a first position where this wall forms a screen between the opening and the treatment space, and a second position where said wall clears the access to the treatment space from the opening.

One aspect of the present invention is to provide a superior steel plate and a method for manufacturing same, the steel plate, as an ultra-thick steel plate, having high strength as well as superb imact toughness low-temperature, and excellent resistance to formation of cracks.

Provided is a high-strength steel sheet including: 0.12% to less than 0.17% of carbon (C), 0.3% to 0.8% of silicon (Si), 2.5% to 3.0% of manganese (Mn), 0.4% to 1.1% of chromium (Cr), 0.01% to 0.3% of aluminum (Al), 0.01% to 0.03% of niobium (Nb), 0.01% to 0.03% of titanium (Ti), 0.001% to 0.003% of boron (B), 0.04% or less of phosphorus (P), 0.01% or less of sulfur (S): 0.01% or less of nitrogen (N), and a balance of iron (Fe) and inevitable impurities. The contents of C, Si, and Al satisfy: [C]+[Si]+[Al])/5≤0.35 wt. A microstructure includes more than 1% to 4% or less of retained austenite, more than 10% to 20% or less of fresh martensite, 5% or less (excluding 0%) of ferrite, more than 50% to 70% or less of tempered martensite, and a balance of bainite.

The present invention is to provide a steel plate with physical properties superior to existing steel plates used in fields such as industrial machinery, especially excellent low-temperature impact toughness along with high strength and high hardness, and a method for manufacturing same.