Patents Assigned to Allegheny Ludlum Steel Corporation
-
Patent number: 4415527Abstract: A method for producing a low carbon ferrous powder melt stock with a sulfur content of less than 5 parts per million is disclosed comprising the steps of atomizing molten steel into a powder, exposing the powder to a temperature of at least 2100.degree. F. in a hydrogen containing atmosphere until the sulfur content has been reduced to the desired level, and cooling the desulfurized powder to ambient temperature in a non-oxidizing atmosphere. During heat treatment an interconnected porosity of at least 10% is maintained for the powder.Type: GrantFiled: December 17, 1980Date of Patent: November 15, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Orville W. Reen
-
Patent number: 4414023Abstract: A ferritic stainless steel alloy is provided which is hot workable and is resistant to thermal cyclic oxidation and scaling at elevated temperatures. The iron-chromium-aluminum alloy contains cerium, lanthanum and other rare earths and is suitable for forming thereon an adherent textured aluminum oxide surface. An oxidation resistant catalytic substrate made from the alloy and a method of making the alloy are also provided.Type: GrantFiled: April 12, 1982Date of Patent: November 8, 1983Assignee: Allegheny Ludlum Steel CorporationInventors: George Aggen, Paul R. Borneman
-
Patent number: 4411714Abstract: A method for improving the magnetic permeability and core loss of grain oriented silicon steel; the improvement in these magnetic properties is achieved by conducting annealing prior to cold rolling at a temperature above the temperature at which transformation to austenite occurs and thereafter quenching said steel.Type: GrantFiled: August 24, 1981Date of Patent: October 25, 1983Assignee: Allegheny Ludlum Steel CorporationInventors: Amitava Datta, Carl P. Stroble
-
Patent number: 4410359Abstract: A process for the production of stainless steel in a top blown oxygen converter wherein the rate of carbon removal during the refining process is improved particularly from the standpoint of minimizing oxidation of other alloying elements such as chromium. This is achieved by introducing oxygen mixed with an inert gas through a tuyere and into the metal being refined either simultaneously during a portion of the oxygen blowing or after the completion of oxygen blowing but in any case it is continued until the required carbon level has been achieved, while the interior of the converter above the liquid level is maintained at subatmospheric pressure.Type: GrantFiled: September 3, 1982Date of Patent: October 18, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Harry L. Bishop, Jr.
-
Patent number: 4409296Abstract: A rapidly quenced, cast metallic strip is disclosed comprising a plurality of dissimilar portions, each portion metallurgically alloy-bonded during casting to adjacent portions along the longitudinal extent of the strip. In the method and apparatus for producing such strip a stream of molten metal is delivered onto a casting surface from a first crucible and at least one additional dissimilar stream of molten metal is delivered onto the casting surface such that a peripheral edge of the dissimilar stream contacts a peripheral edge portion of adjacent dissimilar metal to create a metallurgical alloy-bond therebetween during casting.Type: GrantFiled: October 22, 1980Date of Patent: October 11, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Brian L. Ward
-
Patent number: 4402769Abstract: After autogenous welding of coils of straight-chromium ferritic stainless steel, the weld area is heated to a temperature within the range of about 1325.degree. to 1515.degree. F. and water quenched from elevated temperatures to room temperature to improve the ductility of the weld area so that during subsequent cold rolling cracking of the weld area will be avoided.Type: GrantFiled: December 10, 1982Date of Patent: September 6, 1983Assignee: Allegheny Ludlum Steel CorporationInventors: Jack M. Beigay, Paul T. Lovejoy
-
Patent number: 4399860Abstract: An apparatus for continuously casting strip material is disclosed comprising a tundish having an internal cavity for receiving and holding molten metal and an orifice passage through which the molten metal is delivered from the cavity to a casting surface located within about 0.120 inch of the orifice passage and movable past the orifice passage at a speed of from 200 to 10,000 linear surface feet per minute. The tundish has at least one molten metal resistant upper block and at least one molten metal resistant lower block vertically aligned and secured sufficiently to prevent molten metal in the cavity from passing through the interface of the secured blocks. The orifice passage has a substantially uniform width dimension, of at least about 0.010 inch, throughout the longitudinal extent thereof.Type: GrantFiled: October 3, 1980Date of Patent: August 23, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Robert H. Johns
-
Patent number: 4381660Abstract: A method for preventing weld cracking of autogenous weldments of metastable stainless steel during deforming of the weld, as by stretching; this is achieved by cooling the weld with a pressurized CO.sub.2 spray during the deforming operation.Type: GrantFiled: February 9, 1981Date of Patent: May 3, 1983Assignee: Allegheny Ludlum Steel CorporationInventors: Jack M. Beigay, Remus A. Lula
-
Patent number: 4375371Abstract: A method for induction melting wherein the formation of high melting temperature refractory oxides formed by the reaction of one or more of the raw materials being melted with oxygen is avoided by the introduction of boron.Type: GrantFiled: June 12, 1981Date of Patent: March 1, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Balaji V. Patil
-
Patent number: 4366971Abstract: A corrosion resistant tube assembly is disclosed comprising a corrosion susceptible metal tubing having an outside surface, an inside surface and end surfaces. Peripheral end portions of the tubing are provided with an overlay of corrosion resistant metal extending along a portion of the outside surface and across the end surfaces of the peripheral end portions of the corrosion susceptible metal tubing. The overlay has an inside surface and an outside surface provided with threads at a depth less than that which would expose the outside surface of the corrosion susceptible tubing. The assembly also includes a corrosion resistant, tubular metallic liner having an outside surface disposed adjacent the inside surface of the corrosion susceptible metal tubing, and end surfaces extending beyond the end surfaces of the corrosion susceptible metal tubing.Type: GrantFiled: September 17, 1980Date of Patent: January 4, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Remus A. Lula
-
Patent number: 4367100Abstract: A process for producing grain oriented electromagnetic silicon steel. The process includes the steps of: preparing a melt of silicon steel having, by weight, from 2.5 to 4.0% silicon; casting the steel; hot rolling the steel; cold rolling the steel; decarburizing the steel; applying a substantially non-reactive aluminum hydroxide coating to the steel; and final texture annealing the steel. The annealed steel being characterized by a substantially uniform metallic surface.Type: GrantFiled: October 15, 1979Date of Patent: January 4, 1983Assignee: Allegheny Ludlum Steel CorporationInventor: Clarence L. Miller, Jr.
-
Patent number: 4363709Abstract: A process for removing an oxide scale from the surface of a metallic body is disclosed comprising the steps of providing an electrolyte consisting of an aqueous solution containing about 15 to 25 weight percent sodium sulfate, maintaining the electrolyte at a temperature of at least 150.degree. F., and immersing the metallic body into the electrolyte such that the surface to be descaled is exposed to the electrolyte. During immersion, the metallic body is subjected as the anode to the action of a direct electric current for a period of at least 10 seconds at a current density of at least 3 amperes per square inch.Type: GrantFiled: February 27, 1981Date of Patent: December 14, 1982Assignee: Allegheny Ludlum Steel CorporationInventor: Donald R. Zaremski
-
Patent number: 4360774Abstract: An improved apparatus is disclosed for measuring the surface insulation characteristics of coatings on magnetic materials. This apparatus comprises an insulative button block having a plurality of protruding contact buttons stationarily mounted therein, with each contact button provided with a substantially flat contact surface, and with all contact surfaces lying substantially in the same plane. The apparatus further includes a press for urging the contact surfaces against the coated surface of the magnetic material, the electric circuitry necessary to apply a predetermined voltage potential between the contact surfaces and the magnetic material, and an ammeter to measure the current flow through the coating.Type: GrantFiled: April 7, 1980Date of Patent: November 23, 1982Assignee: Allegheny Ludlum Steel CorporationInventor: Layton D. Crytzer
-
Patent number: 4337101Abstract: A process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at least 1800 (G/O.sub.e) at 10 oersteds. The process includes the steps of preparing a melt of silicon steel containing from 0.02% to 0.06% carbon, from 0.0006% to 0.008% boron, up to 0.01% nitrogen, up to 0.008% aluminum and from 2.5% to 4.0% silicon, casting the steel, hot rolling the steel to hot band gage, annealing the hot band in a temperature range of from 1450.degree.-1650.degree. F., cold rolling the steel to a final gage of about 0.018 inch in one cold reduction, decarburizing the steel, applying a refractory oxide base coating to the steel and texture annealing the steel.Type: GrantFiled: August 18, 1980Date of Patent: June 29, 1982Assignee: Allegheny Ludlum Steel CorporationInventor: Frank A. Malagari, Jr.
-
Patent number: 4330025Abstract: An improved nozzle is disclosed for a strip casting apparatus wherein molten metal is delivered to a casting surface located within about 0.120 inch of the nozzle, and is movable past the nozzle at a speed of from 200 to 10,000 linear surface feet per minute. The improved nozzle comprises a pair of spaced orifice lips substantially parallel to and facing one another, with the spacing being substantially uniform throughout the majority of the longitudinal extent of the nozzle. The peripheral end portions of the orifice lips continuously diverge outwardly from one another for a length of less than about three times the substantially uniform spacing between lips, and for a height of less than about two times the substantially uniform spacing between lips.Type: GrantFiled: September 11, 1980Date of Patent: May 18, 1982Assignee: Allegheny Ludlum Steel CorporationInventor: Robert H. Johns
-
Patent number: 4315776Abstract: An improved method of producing a coil of light gage metallic strip material is disclosed comprising the steps of compressing a metal powder mixture into a cylindrical billet having homogeneous structure, grain size and chemical composition, rotating the billet about its longitudinal axis, and peeling a continuous light gage layer from the exterior surface of the rotating billet by advancing a cutting edge of a cutting tool into subsurface contact with the rotating billet along the full longitudinal extent of the billet.Type: GrantFiled: August 23, 1979Date of Patent: February 16, 1982Assignee: Allegheny Ludlum Steel CorporationInventor: Richard K. Pitler
-
Patent number: 4302658Abstract: A process for improving the mechanical properties of welded silicon steel. The weld heat affected area of welded silicon steel is heat treated while retaining the welded lengths within a clamping fixture so as to restrain movement thereof from the initiation of welding through the completion of the heat treatment.Type: GrantFiled: September 29, 1980Date of Patent: November 24, 1981Assignee: Allegheny Ludlum Steel CorporationInventor: Jack M. Beigay
-
Patent number: 4297132Abstract: An improved method is disclosed for electroslag remelting an electrode of an alloy containing at least one oxide forming ingredient, including melting such electrode in a novel flux composition containing about 1-35% boron oxide, by weight.Type: GrantFiled: February 25, 1980Date of Patent: October 27, 1981Assignee: Allegheny Ludlum Steel CorporationInventors: Balaji V. Patil, Joseph W. Tommaney
-
Patent number: 4291558Abstract: An improved method is provided for reducing hot rolled band to final gage iron-silicon alloy steel strip material while retaining the magnetic properties of the strip material. In this method, the hot rolled band is passed through an intermediate and a final cold rolling operation to accomplish progressive reduction prior to final annealing of the material. The improvement of the present invention comprises heating the material between the intermediate and final cold rolling operations to a temperature and for a time of at least that necessary to recover the cold rolled structure and to relieve residual stresses in the intermediate cold rolled material and less than that at which grains of the material begin to recrystallize.Type: GrantFiled: July 27, 1979Date of Patent: September 29, 1981Assignee: Allegheny Ludlum Steel CorporationInventors: Pat A. Santoli, Howard E. Baybrook
-
Patent number: 4286986Abstract: Careful control of chemistry, and in particular niobium, and of annealing temperatures provides a ferritic stainless steel of improved creep strength. Annealing is performed at a temperature of at least 1900.degree. F., and in certain embodiments, at a temperature no higher than 1990.degree. F.Type: GrantFiled: August 1, 1979Date of Patent: September 1, 1981Assignee: Allegheny Ludlum Steel CorporationInventor: Paul R. Borneman