An apparatus for the off-line drying treatment, or dry out, of an inductor for billets that includes a coil and a protection body made of refractory material that defines a transit channel for the billets.

A steel pipe for a fuel injection pipe has a chemical composition consisting of, by mass %: C: 0.17 to 0.27%, Si: 0.05 to 0.40%, Mn: 0.30 to 2.00%, P: 0.020% or less, S: 0.0100% or less, O: 0.0040% or less, Ca: 0.0010% or less, Al: 0.005 to 0.060%, N: 0.0020 to 0.0080%, Ti: 0.005 to 0.015%, Nb: 0.015 to 0.045%, Cr: 0 to 1.00%, Mo: 0 to 1.00%, Cu: 0 to 0.50%, Ni: 0 to 0.50%, V: 0 to 0.15%, and the balance: Fe and impurities. The metal micro-structure consists substantially of tempered martensite, or tempered martensite and tempered bainite. The hardness is within the range of 350 to 460 HV1. A lattice spacing of a (211) diffraction plane measured by CoKα characteristic X-ray diffraction is 1.1716 Å or less, and a half-value width of the (211) diffraction plane is 1.200° or less. The number density of cementite having a diameter of 50 nm or more is 20/μm.sup.2 or less.

The present invention generally relates to the modification of a deep-drawing sheet blank (P) for electric resistance heating. Generally, the modified sheet blank comprises slits (Z) being made in the edges of the blank (P) transversely to the electric current flow and oriented towards the perimeter of the forming zone (T). The distances between the ends of the slits (Z) and the forming zone (T) perimeter may be equal. The ends of the slits (Z) oriented towards the forming zone perimeter (T) may also be rounded.

A localized annealing process and a part having localized areas with increased ductility produced by the process. The part is formed of hard material, tempered, and/or otherwise hardened such that it meets minimum hardness and ductility requirements. The part further includes localized areas that have increased ductility for workability, which could include various types of deformation. The localized annealing process includes providing a part with low levels of ductility and then annealing localized areas of the part for increased ductility that will need to be machined or attached to another formed part. The annealing process includes placing an electrode on either side of the localized area and generating electricity through the localized area. The material in the localized area is then heated from the electricity to form a more ductile physical structure.

Provided is a hot-band annealing method comprising subjecting a Si-containing hot rolled steel sheet, having an oxidized scale formed on a surface of the steel sheet by hot rolling, to hot-band annealing with a hot-band annealing equipment provided with a heating zone, a soaking zone, a cooling zone, and a rapid heating device at an upstream side of the heating zone and/or in an inlet side of the heating zone, wherein the hot rolled steel sheet is heated by not lower than 50° C. at a heating rate of not less than 15° C./s by using the rapid heating device to improve a descaling property. Also, provided is a descaling method characterized by subjecting the Si-containing hot rolled steel sheet, after the hot-band annealing, to descaling only by pickling without requiring mechanical descaling or heating the steel sheet in the pickling process.

Provided is a hot-band annealing method comprising subjecting a Si-containing hot rolled steel sheet, having an oxidized scale formed on a surface of the steel sheet by hot rolling, to hot-band annealing with a hot-band annealing equipment provided with a heating zone, a soaking zone, a cooling zone, and a rapid heating device at an upstream side of the heating zone and/or in an inlet side of the heating zone, wherein the hot rolled steel sheet is heated by not lower than 50° C. at a heating rate of not less than 15° C./s by using the rapid heating device to improve a descaling property. Also, provided is a descaling method characterized by subjecting the Si-containing hot rolled steel sheet, after the hot-band annealing, to descaling only by pickling without requiring mechanical descaling or heating the steel sheet in the pickling process.

A hot metal gas forming and quenching system and process thereof are provided. The system includes a hydraulic press, a die assembly, a rapid heating module, and a rapid cooling module. The die assembly includes a progressive die realizing the hot gas bulging and rapid cooling of the workpiece. Through the above system and the process, making pipes with uncoated plates has a lower cost than with coated and plated steel plates, with fewer structural defects and process risks. By using a progressive die, a resistance heating process and hot gas bulging and quenching processes are performed in parallel, and the material is loaded progressively, thereby having a fast pace and a greatly improved efficiency. A heating state of parts is fully protected, oxidation is avoided, and no coating is required. After the workpiece is formed, it can be directly welded to a car body without shot blasting.

The disclosure provides a micro control device for simulating the electric thermal field change of a plate/strip, comprising a plate shape simulating test platform, a high current regulating power supply, a current regulating device, a thermal imager, a thermocouple, a non-contact type full field strain gauge, a high-power current control device and an electro-plastic control system; for a plate/strip with large width to thickness ratio and high hardness and brittleness alloy, different numbers of electrodes are arranged laterally along the movable supporting beam. A high-power current control device is used to realize the sub-regional control of the electric field, thermal field and stress field of the plate/strip; at the same time, the movable supporting beam and tension sensor are used to test the working conditions of the plate/strips with different lengths and widths, to simulate the instantaneous synchronous entanglement process between different fields. An electro-plastic control system is used to realize the intelligent closed-loop control of specific working conditions. The device provides a high-precision physical test platform for studying the non-uniform electro-plastic effect of a high width to thickness ratio and high hardness brittle strip during an actual rolling process, and adds a new and high-efficiency adjustment method to the traditional rolling mill system.

The disclosure provides a micro control device for simulating the electric thermal field change of a plate/strip, comprising a plate shape simulating test platform, a high current regulating power supply, a current regulating device, a thermal imager, a thermocouple, a non-contact type full field strain gauge, a high-power current control device and an electro-plastic control system; for a plate/strip with large width to thickness ratio and high hardness and brittleness alloy, different numbers of electrodes are arranged laterally along the movable supporting beam. A high-power current control device is used to realize the sub-regional control of the electric field, thermal field and stress field of the plate/strip; at the same time, the movable supporting beam and tension sensor are used to test the working conditions of the plate/strips with different lengths and widths, to simulate the instantaneous synchronous entanglement process between different fields. An electro-plastic control system is used to realize the intelligent closed-loop control of specific working conditions. The device provides a high-precision physical test platform for studying the non-uniform electro-plastic effect of a high width to thickness ratio and high hardness brittle strip during an actual rolling process, and adds a new and high-efficiency adjustment method to the traditional rolling mill system.

There is provided a hot-stamped body including: a steel base metal; and a metallic layer formed on a surface of the steel base metal, wherein the metallic layer includes: an interface layer that contains, in mass %, Al: 30.0 to 36.0%, has a thickness of 100 nm to 15 μm, and is located in an interface between the metallic layer and the steel base metal; and a principal layer that includes coexisting Zn phases and insular FeAl.sub.2 phases, is located on the interface layer, and has a thickness of 1 μm to 40 μm. This hot-stamped body is excellent in fatigue properties, corrosion resistance, and chipping resistance.