A predetermined composition is had, when a C content is represented by (C %), in a case of (C %) being not less than 0.35% nor more than 0.65%, a volume fraction of pearlite is 64(C %)+52% or more, and in a case of (C %) being greater than 0.65% and 0.85% or less, the volume fraction of pearlite is not less than 94% nor more than 100%, and a structure of the other portion is composed of one or two of proeutectoid ferrite and bainite. Further, in a region to a depth of 1.0 mm from a surface, a volume fraction of pearlite block having an aspect ratio of 2.0 or more is not less than 70% nor more than 95%, and a volume fraction of pearlite having an angle between an axial direction and a lamellar direction on a cross section parallel to the axial direction of 40 or less is 60% or more with respect to all pearlite.

A high-pressure-torsion apparatus (100), comprising a working axis (102), a first anvil (110), a second anvil (120), and an annular body (130). The annular body (130) comprises a first total-loss convective chiller (140), a second total-loss convective chiller (150), and a heater (160). Each of the first total-loss convective chiller (140) and the second total-loss convective chiller (150) is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), is configured to be thermally convectively coupled with a workpiece (190), and is configured to selectively cool the workpiece (190). The heater (160) is positioned between the first total-loss convective chiller (140) and the second total-loss convective chiller (150) along the working axis (102), is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), and is configured to selectively heat the workpiece (190).

A high-pressure-torsion apparatus (100) comprises a working axis (102), a first anvil (110), a second anvil (120), and an annular body (130). The annular body (130) comprises a first conductive chiller (140), a second conductive chiller (150), and a heater (160). Each of the first conductive chiller (140) and the second conductive chiller (150) is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), is configured to be thermally conductively coupled with a workpiece (190), and is configured to selectively cool the workpiece (190). The heater (160) is positioned between the first conductive chiller (140) and the second conductive chiller (150) along the working axis (102), is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), and is configured to selectively heat the workpiece (190).

A high-pressure-torsion apparatus (100) comprises a working axis (102), a first anvil (110), a second anvil (120), and an annular body (130). The annular body (130) comprises a a first recirculating convective chiller (140), a second recirculating convective chiller (150), and a heater (160). Each of the first recirculating convective chiller (140) and the second recirculating convective chiller (150) is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), is configured to be thermally convectively coupled with a workpiece (190), and is configured to selectively cool the workpiece (190). The heater (160) is positioned between the first recirculating convective chiller (140) and the second recirculating convective chiller (150) along the working axis (102), is translatable between the first anvil (110) and the second anvil (120) along the working axis (102), and is configured to selectively heat the workpiece (190).

A method for producing an austempered steel is provided. The method includes subjecting a steel alloy having a silicon content of 1.5 to 4.4 weight percent and a carbon content of 0.3 to 0.8 weight percent to continuous cooling followed by annealing. The cooling rate is initially sufficiently fast to prevent predominant formation of proeutectoid ferrite or pearlite, while subsequently at intermediate temperatures, the cooling rate is sufficiently slow to allow a transformation of the austenite to mainly ausferrite during cooling. The annealing is able to complete the transformation of carbon enriched austenite to ausferrite and to temper any martensite previously formed. The method results in the cost-efficient production of one or more continuously cooled and annealed austempered steel components or semi-finished products having mainly an ausferritic microstructure.

A quench and temper steel alloy is disclosed having the following composition in weight percent.

TABLE-US-00001 C 0.1-0.4 Mn 0.1-1.0 Si 0.1-1.2 Cr 9.0-12.5 Ni 3.0-4.3 Mo 1-2 Cu 0.1-1.0 Co 1-4 W 0.2 max. V 0.1-0.6 Ti 0.1 max. Nb up to 0.01 Ta up to 0.01 Al 0-0.25 N 0.1-0.35 Ce 0.006 max. La 0.006 max.
The balance of the alloy is iron and the usual impurities found in similar grades of quench and temper steels intended for similar use or service, including not more than about 0.01% phosphorus and not more than about 0.010% sulfur. A quenched and tempered steel article made from this alloy is also disclosed. Further disclosed is a method of making the alloy.

Provided is a coolant spray module system for a heat treatment metal product, comprising: a first coolant spray module (1), wherein the first coolant spray module (1) comprises a first module housing (10), a first module cover (20), and a first nozzle (30), wherein the first nozzle (30) is fixed between the first module housing (10) and the first module cover (20) by first nozzle fixing blocks (13) and second nozzle fixing blocks (23), wherein the coolant spray module system sprays the coolant onto the heat treatment metal product to quench and clean the heat treatment metal product.

A thin gauge wear-resistant steel sheet, including the following chemical elements expressed in percentage by weight: 0.15-0.20 wt. % of carbon; 1.2-1.8 wt. % of manganese; 0.1-0.40 wt. % of copper; 0.15-0.30 wt. % of molybdenum; 0.20-0.40 wt. % of chromium; 0.03-0.06 wt. % of niobium; 0.01-0.03 wt. % of titanium; 0.0006-0.0015 wt. % boron; less than 0.015 wt. % of phosphorus; less than 0.010 wt. % of sulphur; and the balance being ferrum and unavoidable impurities, wherein the thickness of the steel sheet is in a range of 3.0 to 8 mm.

The present invention relates to a torsional severe plastic deformation method for a metal bar to which surface polishing is applied to the metal bar to improve the mechanical properties of the metal bar. According to an embodiment of the present invention, there is provided a torsional severe plastic deformation method for a metal bar, which includes: applying torsion to a metal bar; and removing a surface defect on the surface of the metal bar, the surface defect being caused by the applying of torsion, wherein the removing of the surface defect is carried out in a continuous manner in which the removing of the surface defect is performed together with the applying of torsion or in a discontinuous manner in which the applying of torsion is temporarily stopped and then the applying of torsion is performed, and the removing of a surface defect increases the amount of torsional rotation or the shear strain applied to the metal bar.

The present invention discloses a 400 MPa corrosion-resistant steel bar and a production method thereof. The steel bar includes the following chemical ingredients: 9.5-10.4% of Cr, 1.0-1.2% of Mo, 0.3-0.6% of Mn, 0.01-1% of Ni, 0.01-0.5% of Cu, at most 0.014% of C, at most 0.004% of N, 0.01-0.05% of Nb, 0.2-0.6% of Si, and the balance of Fe, where Cr+Mo+0.5Mn+0.35Ni+0.25Cu is 11.1-12.2%, and C+N+0.3Si+Mn+1.8Nb is 0.4-0.8%.