This steel sheet has a predetermined chemical composition, at a depth position of ¼ of a sheet thickness from a surface, an area fraction of GAM.sub.0.5-1.7 is 50% or more and 100% or less, an area fraction of GAM.sub.>1.7 is 0% or more and 20% or less, an area fraction of GAM.sub.≤0.5 is 0% or more and less than 50%, an area fraction of residual austenite is 0% or more and less than 4%, a total area fraction of the residual austenite, fresh martensite, cementite and pearlite is 0% or more and 10% or less, an average grain size is 15.0 μm or less, an average dislocation density is 1.0×10.sup.14/m.sup.2 or more and 4.0×10.sup.15/m.sup.2 less, a total of pole densities of {211}<011> and {332}<113> in a thickness middle portion is 12.0 or less, and a tensile strength is 980 MPa or more.

This steel sheet has a predetermined chemical composition, at a depth position of ¼ of a sheet thickness from a surface, an area fraction of GAM.sub.0.5-1.7 is 50% or more and 100% or less, an area fraction of GAM.sub.>1.7 is 0% or more and 20% or less, an area fraction of GAM.sub.≤0.5 is 0% or more and less than 50%, an area fraction of residual austenite is 0% or more and less than 4%, a total area fraction of the residual austenite, fresh martensite, cementite and pearlite is 0% or more and 10% or less, an average grain size is 15.0 μm or less, an average dislocation density is 1.0×10.sup.14/m.sup.2 or more and 4.0×10.sup.15/m.sup.2 less, a total of pole densities of {211}<011> and {332}<113> in a thickness middle portion is 12.0 or less, and a tensile strength is 980 MPa or more.

An internal oxidation starting temperature, estimation device estimates an internal oxidation starting temperature which is a minimum temperature required for an internal oxide layer to grow on a surface of an easily oxidizable element-containing hot-rolled steel sheet including Si, Mn, or Al or any combination thereof. The internal oxidation starting temperature estimation device includes an internal, oxidation starting temperature estimation unit that estimates the internal oxidation starting temperature on the basis of concentrations of the Si, the Mn, and the Al included in the easily oxidizable element-containing hot-rolled steel sheet.

This hot-rolled steel sheet has a predetermined chemical composition, and in a case where the thickness is denoted by t, the metallographic structure at a t/4 position from the surface contains one or both of tempered martensite and lower bainite at a volume percentage of 90% or more, the tensile strength is 980 MPa or more, and the average Ni concentration on the surface is 7.0% or more.

Disclosed is a tubular core on which sheets of metal or other material can be wound and supported, for shipment, handling and dispersal, and a method for forming the core. The core comprises a metal sheet or strip which has a rectangular-ribbed cross-sectional profile comprising rectangular, flat ribs, and which is wound spirally into a tubular configuration. The core is formed by passing the strip through a plurality of roll-forming stands, to progressively form sections of the ribs and progressively define the sections into the rectangular ribbed profile in which the flat ribs collectively form a support surface for the sheets which are to be wound on the core.

The present disclosure discloses a steel strip coiling temperature control method, a steel strip coiling temperature control device and a steel strip processing system, which relate to the technical field of steel strip production. The method comprises: seeking a corresponding speed compensation coefficient according to a target thickness of the steel strip and a target temperature parameter; seeking a corresponding speed gain coefficient from a second correspondence table according to a steel strip speed; correcting the steel strip speed based on the speed compensation coefficient and the speed gain coefficient to obtain a corrected steel strip speed; and adjusting a cooling efficiency of a laminar flow cooling apparatus according to the corrected steel strip speed. With the method, the cooling efficiency of the laminar flow cooling apparatus can be dynamically adjusted according to the steel strip speed, thereby solving the problem that that there is a great difference in coiling temperature between a tail section of the steel strip and a front section of the steel strip caused by the steel strip throwing process, and reducing the amount of cutting loss of the steel strip.

The present disclosure discloses a steel strip coiling temperature control method, a steel strip coiling temperature control device and a steel strip processing system, which relate to the technical field of steel strip production. The method comprises: seeking a corresponding speed compensation coefficient according to a target thickness of the steel strip and a target temperature parameter; seeking a corresponding speed gain coefficient from a second correspondence table according to a steel strip speed; correcting the steel strip speed based on the speed compensation coefficient and the speed gain coefficient to obtain a corrected steel strip speed; and adjusting a cooling efficiency of a laminar flow cooling apparatus according to the corrected steel strip speed. With the method, the cooling efficiency of the laminar flow cooling apparatus can be dynamically adjusted according to the steel strip speed, thereby solving the problem that that there is a great difference in coiling temperature between a tail section of the steel strip and a front section of the steel strip caused by the steel strip throwing process, and reducing the amount of cutting loss of the steel strip.

A heat treated cold rolled steel sheet with the following elements, 0.1%≤C≤0.2%; 1.2%≤Mn≤2.2%; 0.05%≤Si≤0.6%; 0.001%≤Al≤0.1%; 0.01%≤Cr≤0.5 %; 0%≤S≤0.09%; 0%≤P≤0.09%; 0%≤N≤0.09%; 0%≤Mo≤0.5%; 0%≤Ti≤0.1%; 0%≤Nb≤0.1%; 0%≤V≤0.1%; 0%≤Ni≤1%; 0%≤Cu≤1%; 0%≤Ca≤0.005%; 0%≤B≤0.05%; the remainder composition being composed of iron and unavoidable impurities caused by processing, the microstructure of the steel having, by area percentage, 60% to 85% of tempered martensite, a cumulated amount of ferrite and bainite of 15% to 38%, an optional amount of residual austenite of 0% to 5% and an optional amount of fresh martensite of 0 to 5%.

A heat treated cold rolled steel sheet with the following elements, 0.1%≤C≤0.2%; 1.2%≤Mn≤2.2%; 0.05%≤Si≤0.6%; 0.001%≤Al≤0.1%; 0.01%≤Cr≤0.5 %; 0%≤S≤0.09%; 0%≤P≤0.09%; 0%≤N≤0.09%; 0%≤Mo≤0.5%; 0%≤Ti≤0.1%; 0%≤Nb≤0.1%; 0%≤V≤0.1%; 0%≤Ni≤1%; 0%≤Cu≤1%; 0%≤Ca≤0.005%; 0%≤B≤0.05%; the remainder composition being composed of iron and unavoidable impurities caused by processing, the microstructure of the steel having, by area percentage, 60% to 85% of tempered martensite, a cumulated amount of ferrite and bainite of 15% to 38%, an optional amount of residual austenite of 0% to 5% and an optional amount of fresh martensite of 0 to 5%.

Methods, apparatus, systems, and computer-readable media are provided for tracking amounts of wires provided to a winding head during a winding operation of a wire distribution system. The wires can be tracked using one or more wire tracking devices that can be disposed at one or more locations within the wire distribution system. The wire tracking devices can provide information related to the amounts of wires and the types of wires being used to wind about a winding head/form. The information can be used to check for errors during a winding operation and indicate the progress of the winding operation. The information can also be used to update wire-availability data to reflect the amount of wire that has been provided during the winding operation.