Provided is a wire rod having enhanced strength and impact toughness comprising, by wt %, carbon (C): 0.05% to 0.15%, silicon (Si): 0.2% or less, manganese (Mn): 3.0% to 4.0%, phosphorus (P): 0.020% or less, sulfur (5):0.020% or less, boron (B): 0.0010% to 0.0030%, titanium (Ti): 0.010% to 0.030%, nitrogen (N): 0.0050% or less, aluminum (Al): 0.010% to 0.050%, iron (Fe) as a residual component thereof, and other unavoidable impurities. A microstructure includes bainitic ferrite in an area fraction of 90% or more, and a martensite/austenite (M/A) constituent as a residual component thereof.

A manufacturing method for strip casting 700 MPa-grade high strength atmospheric corrosion-resistant steel, comprising the following steps: 1) smelting, where the chemical composition of a molten steel in terms of weight percentage is that C is between 0.03-0.1%, Si≦0.4%, Mn is between 0.75-2.0%, P is between 0.07-0.22%, S≦0.01%, N≦0.012%, Cu is between 0.25-0.8%, Cr is between 0.3-0.8%, and Ni is between 0.12-0.4%, additionally, also comprised is at least one micro-alloying element among Nb, V, Ti, and Mo, where Nb is between 0.01-0.1%, V is between 0.01-0.1%, Ti is between 0.01-0.1%, and Mo is between 0.1-0.5%, and where the remainder is Fe and unavoidable impurities; 2) strip casting, where a 1-5 mm-thick cast strip is casted directly; 3) cooling the cast strip, where the cooling rate is greater than 20° C./s; 4) online hot rolling the cast strip, where the hot rolling temperature is between 1050-1250° C., where the reduction rate is between 20-50%, and where the deformation rate is >20s.sup.−1; austenite online recrystallizing after hot rolling, where the thickness of the hot rolled strip is between 0.5-3.0 mm; and, 5) cooling and winding, where the cooling rate is between 10-80° C./s, and where the winding temperature is between 520-670° C. The microscopic structure of a steel strip acquired is primarily constituted by evenly distributed bainite and acicular ferrite.

A manufacturing method for strip casting 700 MPa-grade high strength atmospheric corrosion-resistant steel, comprising the following steps: 1) smelting, where the chemical composition of a molten steel in terms of weight percentage is that C is between 0.03-0.1%, Si≦0.4%, Mn is between 0.75-2.0%, P is between 0.07-0.22%, S≦0.01%, N≦0.012%, Cu is between 0.25-0.8%, Cr is between 0.3-0.8%, and Ni is between 0.12-0.4%, additionally, also comprised is at least one micro-alloying element among Nb, V, Ti, and Mo, where Nb is between 0.01-0.1%, V is between 0.01-0.1%, Ti is between 0.01-0.1%, and Mo is between 0.1-0.5%, and where the remainder is Fe and unavoidable impurities; 2) strip casting, where a 1-5 mm-thick cast strip is casted directly; 3) cooling the cast strip, where the cooling rate is greater than 20° C./s; 4) online hot rolling the cast strip, where the hot rolling temperature is between 1050-1250° C., where the reduction rate is between 20-50%, and where the deformation rate is >20s.sup.−1; austenite online recrystallizing after hot rolling, where the thickness of the hot rolled strip is between 0.5-3.0 mm; and, 5) cooling and winding, where the cooling rate is between 10-80° C./s, and where the winding temperature is between 520-670° C. The microscopic structure of a steel strip acquired is primarily constituted by evenly distributed bainite and acicular ferrite.

A helicoid conveyor screw manufactured from alloy steel and tempered by electromagnetic induction or flame used to convey abrasive granular products in the process of screw rotation under high friction and wear. Its inventive principle is related to the method for obtaining it by alloying steel with the chemical element Boron (B) and heat treating it, which results in greater hardness and durability of the flight.

A helicoid conveyor screw manufactured from alloy steel and tempered by electromagnetic induction or flame used to convey abrasive granular products in the process of screw rotation under high friction and wear. Its inventive principle is related to the method for obtaining it by alloying steel with the chemical element Boron (B) and heat treating it, which results in greater hardness and durability of the flight.

Provided are a method and apparatus for uniformly controlling the strip temperature of the rapid cooling section of a continuous annealing line. A plurality of sets of cooling nozzle blocks for controlling the strip temperature is installed at the front and back sides of the strip, and is divided into lengthwise flow control nozzle blocks and widthwise flow control nozzle blocks. Strip center temperature meters and widthwise direction temperature meters are installed at the intake and discharge sides of the rapid cooling section. Temperatures obtained using the strip center temperature meters and the width direction temperature meters are used to respectively control the spraying of mist for the lengthwise flow control nozzle blocks and the widthwise flow control nozzle blocks in order to uniformly control the strip temperature and minimize changes in the flatness of the strip. The widthwise temperature meters at the intake and discharge ends of the rapid cooling section of the continuous annealing line are used to detect the temperature. Feedback/feedforward control technique can be used to uniformly control the widthwise temperature of the strip through flow rate control over mist sprayed in the widthwise direction of the rapid cooling section.

Provided are a method and apparatus for uniformly controlling the strip temperature of the rapid cooling section of a continuous annealing line. A plurality of sets of cooling nozzle blocks for controlling the strip temperature is installed at the front and back sides of the strip, and is divided into lengthwise flow control nozzle blocks and widthwise flow control nozzle blocks. Strip center temperature meters and widthwise direction temperature meters are installed at the intake and discharge sides of the rapid cooling section. Temperatures obtained using the strip center temperature meters and the width direction temperature meters are used to respectively control the spraying of mist for the lengthwise flow control nozzle blocks and the widthwise flow control nozzle blocks in order to uniformly control the strip temperature and minimize changes in the flatness of the strip. The widthwise temperature meters at the intake and discharge ends of the rapid cooling section of the continuous annealing line are used to detect the temperature. Feedback/feedforward control technique can be used to uniformly control the widthwise temperature of the strip through flow rate control over mist sprayed in the widthwise direction of the rapid cooling section.

Disclosed is a method for producing steel for blades having a metal composition consisting of, by mass, 0.55% to 0.8% C, not more than 1.0% Si, not more than 1.0% Mn, 12.0% to 14.0% Cr, not more than 1.0% Mo, not more than 1.0% Ni, and the balance Fe with impurities, comprising: a batch annealing step for batch annealing a material to be cold rolled having the metal composition at a temperature of 500° C. to 700° C. for 3 to 30 hours; a continuous annealing step for continuously annealing the batch annealed material for 5 to 30 minutes so that the batch annealed material is heated to at least an Ac1 transformation point of the metal composition step to obtain a continuously annealed material; and a cold rolling step for cold rolling the continuously annealed material, wherein the continuous annealing step and the cold rolling step are performed at least once, respectively.

A thermal-assisted method deforms plastically a high-strength material using a high-intensive heat source. The high-strength material may be a cold-rolled sheet aluminum of strength greater than 300 megapascal (MPa) or a cold-rolled sheet steel of strength greater than 1000 MPa. The cold-rolled sheet metal is heated just before bending to a temperature near or above the critical temperature for the material and is followed by rapid quenching after bending.

A thermal-assisted method deforms plastically a high-strength material using a high-intensive heat source. The high-strength material may be a cold-rolled sheet aluminum of strength greater than 300 megapascal (MPa) or a cold-rolled sheet steel of strength greater than 1000 MPa. The cold-rolled sheet metal is heated just before bending to a temperature near or above the critical temperature for the material and is followed by rapid quenching after bending.