The invention relates to a cooling device (100) for cooling at least one element (150, 151) passing through said device, comprising a metal block (115), having a first side and a second side, and comprising a cooling channel (130) for cyrogenic gas. The at least one element (150, 151) can be guided along the sides of the first side of the metal block (115), the cooling channel (130) is at least partially in heat conductive connection with the second side of the metal block (115), and the cooling channel (130) has an attachment (131) on a first end for the entry of cryogenic gas and an attachment on a second end for the exit of cryogenic gas. The invention also comprises a hardening device having such a cooling device (100) and a method for cooling at least one element (150, 151) passing through said device.

The invention relates to a device for water spray quenching that includes (i) a quenching chamber designed and set up to receive metallic workpieces, with a batch of volume V.sub.0 of 0.045 to 3.5 m.sup.3 and (ii) at least one atomizer which is configured to atomize water in air or nitrogen and is fluidically connected to the quenching chamber; in which the at least one atomizer and the device are designed and set up to generate a spray mist with a water content of 2.5 to 40 vol. % and a Sauter mean diameter of 20 to 2000 m and also a spray mist flow through the batch volume V.sub.0 of 0.05 to 25 m.sup.3/s.

The invention relates to a device for water spray quenching that includes (i) a quenching chamber designed and set up to receive metallic workpieces, with a batch of volume V.sub.0 of 0.045 to 3.5 m.sup.3 and (ii) at least one atomizer which is configured to atomize water in air or nitrogen and is fluidically connected to the quenching chamber; in which the at least one atomizer and the device are designed and set up to generate a spray mist with a water content of 2.5 to 40 vol. % and a Sauter mean diameter of 20 to 2000 m and also a spray mist flow through the batch volume V.sub.0 of 0.05 to 25 m.sup.3/s.

A method of making a forged, martensitic, stainless steel alloy is provided. The alloy is a forged preform of martensitic, pitting corrosion resistant stainless steel alloy comprising, by weight: 12.0 to 16.0 percent chromium; greater than 16.0 to 20.0 percent cobalt, 6.0 to 8.0 percent molybdenum, 1.0 to 3.0 percent nickel, 0.02 to 0.04 percent carbon; and the balance iron and incidental impurities. The alloy has a microstructure that comprises a retained austenite phase less than or equal to 2 percent by volume of the microstructure. The method heats the preform to a solutionizing temperature to form a solutionized microstructure. The preform is cooled with a liquid to room temperature. The preform is immersed in a cryo-liquid to transform the retained austenite phase in the microstructure to martensite. The preform is heated to a temperature of less than 600° F. for a time sufficient to form a tempered forged preform.

A method of making a forged, martensitic, stainless steel alloy is provided. The alloy is a forged preform of martensitic, pitting corrosion resistant stainless steel alloy comprising, by weight: 12.0 to 16.0 percent chromium; greater than 16.0 to 20.0 percent cobalt, 6.0 to 8.0 percent molybdenum, 1.0 to 3.0 percent nickel, 0.02 to 0.04 percent carbon; and the balance iron and incidental impurities. The alloy has a microstructure that comprises a retained austenite phase less than or equal to 2 percent by volume of the microstructure. The method heats the preform to a solutionizing temperature to form a solutionized microstructure. The preform is cooled with a liquid to room temperature. The preform is immersed in a cryo-liquid to transform the retained austenite phase in the microstructure to martensite. The preform is heated to a temperature of less than 600° F. for a time sufficient to form a tempered forged preform.

The invention relates to a steel wire suitable for making a spring or medical wire products which remarkably improve the performance of conventional stainless steel wire. The steel comprises (in wt. %): C: 0.02 to 0.15, Si: 0.1 to 0.9, Mn: 0.8 to 1.6, Cr 16 to 20, Ni: 7.5 to 10.5, Mo: ≤3, Al: 0.5 to 2.5, Ti: ≤0.15, N: ≤0.05, optional elements, and impurities, balance Fe, wherein the total amount of Cr and Ni is 25 to 27 wt. %, and wherein the steel has a microstructure including, in volume % (vol. %), martensite: 40 to 90, austenite: 10 to 60, and delta ferrite: ≤5.

A process for preparing a multi-thickness welded steel vehicle rail, the process comprises the steps of: (a) forming a first tube having a first outer diameter, an inner diameter and a first wall thickness; (b) forming a second tube having the first outer diameter, a second inner diameter and a second wall thickness different than the first wall thickness; (c) swaging a first end of the first tube to a second outer diameter less than the second inner diameter of the second tube; (d) inserting the swaged first end of the first tube into an end of the second tube to form a joint; (e) welding the first tube and the second tube together to form a weld at the joint to form a tube blank with a heat affected zone of lower metal strength in the area of the weld; (f) preheating the tube blank to create a common crystalline microstructure along a length of the tube blank; (g) introducing the tube blank into a blow molding tool having inner molding walls; (h) molding the tube blank at an elevated temperature by expanding the tube blank against the inner molding walls of the molding tool by injecting a pressurized medium into an interior cavity of the tube blank; and (i) quenching the tube blank by replacing the pressurized medium with a cooling medium through the molding tool and the tube blank to achieve a rapid cooling effect on the tube blank and to create a completed vehicle rail with essentially uniform material strength across the weld. A completed vehicle rail has an overlapped welded structure and uniform microcrystalline structure along the length of the rail.

A bearing assembly, particularly refrigerant lubricated bearing assembly, having at least an inner ring and an outer ring, which are rotatable to each other. At least one bearing ring is made from a nitrogen-alloyed stainless steel having a nitrogen (N) content of more than 0.6 wt.-%. A method for manufacturing such a bearing ring is also provided.

A method of manufacturing a part includes additively manufacturing, with an additive manufacturing machine, at least one wall of the part having a first thickness from powder in a powder bed, and peening, with a peening system, at least a portion of the wall of the part. The peening induces plastic deformation in the portion of the wall. The portion of the wall that is peened has a second thickness less than the first thickness of the wall prior to peening. The second thickness of the portion of the wall may be less than a minimum thickness limit achievable by the additive manufacturing machine.

Methods for forming carbon-based lubricious and/or wear-protective films in situ on the surface of steel alloys are provided. The methods use chromium-containing steel alloys, molybdenum-containing steel alloys, and steel alloys that contain both copper and nickel. When such alloys are subjected to a rubbing motion in the presence of a hydrocarbon fluid, the chromium, molybdenum, copper, and nickel in the steel alloy catalyzes the formation of solid carbon-containing films that reduce the friction, wear, or both of the contacting surfaces.