The present invention provides a non-magnetic stainless steel with high strength and corrosion resistance and a preparation method thereof. The non-magnetic stainless steel composed of the following components according to percentage by weight: 17%<Cr<23%, 17%<Mn<23%, 17%<Co<23%, 0.5%<Si <3%, and the balance of iron and inevitable impurities thereof. The preparation method includes: (1) melting a raw material and casting it to a mold to obtain a stainless steel block; (2) homogenizing the stainless steel block at 1,100-1,250° C. for 6-12 hours; (3) forging the homogenized stainless steel block at 1,050-1,150° C. with a final forging temperature of 850-950° C. to obtain a plate having a thickness of 5-15 mm; and (4) holding the forged plate at 1,000-1,250° C. for 10-30 minutes and then put it in water for quenching. The non-magnetic stainless steel of the present invention has superior pitting corrosion resistance and mechanical properties. After a certain heat treatment process, the stainless steel has ultrahigh strength, hardness and toughness and excellent corrosion resistance and low-temperature toughness, and can be used for preparing an outer cladding material of a superconductor in the nuclear fusion industry.

Provided is steel for a wind power gear with improved purity and reliability. The chemical components thereof comprise, in percentages by mass: 0.15-0.19% of C, ≤0.4% of Si, 0.5-0.7% of Mn, ≤0.012% of P, ≤0.006% of S, 1.5-1.8% of Cr, 0.28-0.35% of Mo, 1.4-1.7% of Ni, and 0.02-0.04% of Al, with the balance being Fe and inevitable impurities. A smelting method therefor comprises adding raw materials to a converter for primary melting, transferring same to a refining furnace for refining, carrying out continuous casting after vacuum degassing, and transferring same to a gas protection furnace for electroslag remelting. According to the present invention, a pure electroslag master batch is obtained by continuous casting, and the purity of the material is further improved by means of an electroslag remelting procedure; and the prepared steel material is used in a wind power gear, such that the flaw detection pass rate is significantly increased, large-particle inclusions in the steel material are significantly reduced, and the inclusions are fine and dispersed.

Provided are a plated steel sheet for hot press forming including: a base steel sheet containing, by wt%, 0.14 to 0.5% of C, 0.001 to 1% of Si, 0.3 to 4% of Mn, 0.001 to 0.015% of P, 0.0001 to 0.02% of S, 0.001 to 0.1% of Al, 0.001 to 1% of Cr, 0.001 to 0.02% of N, 0.1% or less of Ti, 0.01% or less of B, 0.005 to 0.1% of Sb, and a balance of Fe and unavoidable impurities; an aluminum or aluminum alloy plating layer provided on at least one surface of the base steel sheet; and a Sb-rich layer provided between the base steel sheet and the plating layer, wherein the plated steel sheet for hot press forming satisfies the following Relational Expressions 1-1 and 1-2, a hot press formed member manufactured using the same, and methods for manufacturing the plated steel sheet for hot press forming and the hot press formed member.

[00001]$\begin{array}{cc}\frac{S{b}_{\max }}{S{b}_{coat}}\ge 1.2& \text{­­­[Relational Expression 1-1]}\end{array}$

[00002]$\begin{array}{cc}\frac{\left(S{b}_{\max }-S{b}_{coat}\right)}{2}\times \text{Δ}t\ge 0.008& \text{­­­[Relational Expression 1-2]}\end{array}$

[In Relational Expressions 1-1 and 1-2, Sb.sub.coat represents an average content of Sb in the plating layer, and a unit thereof is wt%, Sb.sub.max represents a maximum value of a content of Sb in the Sb-rich layer, and a unit thereof is wt%, and Δt represents a linear distance from a boundary between the plating layer and the Sb-rich layer to a point where Sb.sub.max is measured, and a unit thereof is .Math.m.]

Provided are a plated steel sheet for hot press forming including: a base steel sheet containing, by wt%, 0.14 to 0.5% of C, 0.001 to 1% of Si, 0.3 to 4% of Mn, 0.001 to 0.015% of P, 0.0001 to 0.02% of S, 0.001 to 0.1% of Al, 0.001 to 1% of Cr, 0.001 to 0.02% of N, 0.1% or less of Ti, 0.01% or less of B, 0.005 to 0.1% of Sb, and a balance of Fe and unavoidable impurities; an aluminum or aluminum alloy plating layer provided on at least one surface of the base steel sheet; and a Sb-rich layer provided between the base steel sheet and the plating layer, wherein the plated steel sheet for hot press forming satisfies the following Relational Expressions 1-1 and 1-2, a hot press formed member manufactured using the same, and methods for manufacturing the plated steel sheet for hot press forming and the hot press formed member.

[00001]$\begin{array}{cc}\frac{S{b}_{\max }}{S{b}_{coat}}\ge 1.2& \text{­­­[Relational Expression 1-1]}\end{array}$

[00002]$\begin{array}{cc}\frac{\left(S{b}_{\max }-S{b}_{coat}\right)}{2}\times \text{Δ}t\ge 0.008& \text{­­­[Relational Expression 1-2]}\end{array}$

[In Relational Expressions 1-1 and 1-2, Sb.sub.coat represents an average content of Sb in the plating layer, and a unit thereof is wt%, Sb.sub.max represents a maximum value of a content of Sb in the Sb-rich layer, and a unit thereof is wt%, and Δt represents a linear distance from a boundary between the plating layer and the Sb-rich layer to a point where Sb.sub.max is measured, and a unit thereof is .Math.m.]

A method for producing steel strip, in particular hot strip in the form of coiled coils or in the form of folded individual sheets, in which a steel melt is first produced, this is then formed into a strand in a continuous casting system, the strand is then fed into a heating unit and the heated strand is then rolled into hot strip in a subsequent rolling mill. The casting of the strand, the passage through the heating unit, and the rolling take place in a continuous process. To be able to produce hot-rolled steel strips in the most energy-efficient way possible and to make these strips available for further processing into high-quality cold-rolled and, if necessary, coated strips, the invention provides that, first of all, a steel melt is produced.

A method for producing steel strip, in particular hot strip in the form of coiled coils or in the form of folded individual sheets, in which a steel melt is first produced, this is then formed into a strand in a continuous casting system, the strand is then fed into a heating unit and the heated strand is then rolled into hot strip in a subsequent rolling mill. The casting of the strand, the passage through the heating unit, and the rolling take place in a continuous process. To be able to produce hot-rolled steel strips in the most energy-efficient way possible and to make these strips available for further processing into high-quality cold-rolled and, if necessary, coated strips, the invention provides that, first of all, a steel melt is produced.

A method for manufacturing thin-specification high-Ti wear-resistant steel NM450 comprises the steps of preparing melted iron in a blast-furnace, preprocessing the melted iron, smelting the melted iron in a converter, refining the melted steel in a LF furnace, refining the melted steel in a RH furnace, conventional slab continuous casting, heating the slab in a heating furnace, dephosphorizing the slab by high-pressure water, heating the slab in a hot continuous rolling mill, performing ultra fast cooling, reeling, flattening, heating, quenching, tempering and finishing.

The present disclosure belongs to the technical field of welding materials, and in particular relates to a Fe—Ni based alloy welding wire for welding 800H alloy and a preparation method thereof and a method for welding 800H alloy. The Fe—Ni based alloy welding wire for welding 800H alloy provided by the present disclosure has a reasonable chemical components, and after being used to weld 800H alloy, the obtained weld has a tensile strength of 557.6 MPa and an elongation of 37.5% at ambient temperature, and has a tensile strength of 420 MPa and an elongation of 17.25% at a temperature of 650° C.

The present disclosure belongs to the technical field of welding materials, and in particular relates to a Fe—Ni based alloy welding wire for welding 800H alloy and a preparation method thereof and a method for welding 800H alloy. The Fe—Ni based alloy welding wire for welding 800H alloy provided by the present disclosure has a reasonable chemical components, and after being used to weld 800H alloy, the obtained weld has a tensile strength of 557.6 MPa and an elongation of 37.5% at ambient temperature, and has a tensile strength of 420 MPa and an elongation of 17.25% at a temperature of 650° C.

Provided in the present application are a rare-earth microalloyed steel and a control process. The steel has a special microstructure, and the microstructure comprises a rare earth-rich nanocluster having a diameter of 1-50 nm. The nanocluster has the same crystal structure type as a matrix. The rare earth-rich nanocluster inhibits the segregation of the elements S, P and As on a grain boundary, and obviously improves the fatigue life of the steel. In addition, a rare-earth solid solution also directly affects a phase change dynamics process so that the diffusion-type phase change starting temperature in the steel changes at least to 2° C., and even changes to 40-60° C. in some kinds of steel, thereby greatly improving the mechanical properties thereof, and providing a foundation for the development of more kinds of high-performance steel.