Patents Assigned to Allegheny Ludlum Steel Corporation
  • Patent number: 4277374
    Abstract: A system comprising a ferritic stainless steel substrate having a tightly adherent oxide coating and a catalytic material thereupon. The ferritic stainless steel is of a chemistry which forms a tightly adherent non-spalling scale suitable for application of a catalytic bearing material. It consists essentially of, by weight, up to 26% chromium, from 1 to 8% aluminum, from 0.02 to 2% hafnium, up to 0.3% yttrium, up to 0.1% carbon, up to 2% silicon, balance essentially iron.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: July 7, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventors: Remus A. Lula, George Aggen
  • Patent number: 4277530
    Abstract: A laminated article for electrical applications is disclosed which comprises at least two sheets of electrically isolated electrical steel each having a thickness of less than 0.020 inch, and an adhesive between adjacent sheets bonding the adjacent sheets to one another without creating significant compressive stress in the plane of the sheets. The adhesive is characterized by substantially instantaneous bonding at a temperature less than 750.degree. F.
    Type: Grant
    Filed: September 10, 1979
    Date of Patent: July 7, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Robert F. Miller
  • Patent number: 4260418
    Abstract: An improved method for producing a low carbon, low nitrogen ferrochromium containing molybdenum. The method comprises the steps of blending particles of high carbon ferrochromium and particles of an oxygen and molybdenum bearing compound, heat treating the blend in a vacuum at temperatures of 1600.degree. F. or over, and pressures of 10 torr or below, and cooling the blend. The improvement of this invention comprises the use of a high carbon ferrochromium and an oxygen and molybdenum bearing compound as the original materials.
    Type: Grant
    Filed: September 4, 1979
    Date of Patent: April 7, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Orville W. Reen
  • Patent number: 4260415
    Abstract: An improved method of refining molten metal is disclosed comprising the steps of injecting a mixture of oxygen and an inert gas below the surface of molten metal at a high oxygen to inert gas ratio while utilizing from about 2.5 to 12% of the injected inert gas to shroud the remainder of the injected gaseous mixture. The oxygen to inert gas ratio is progressively decreased as the carbon content in the molten metal decreases and the temperature of the molten metal increases. The improvement of the present invention comprises supplying dry air to the remainder of the injected gaseous mixture in a quantity sufficient for the nitrogen in the dry air to fulfill the inert gas requirements for the remainder of the injected gaseous mixture, and for the oxygen in the dry air to fulfill at least a portion of the oxygen requirements for the injected gaseous mixture.
    Type: Grant
    Filed: December 12, 1979
    Date of Patent: April 7, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Richard P. Simmons
  • Patent number: 4255494
    Abstract: A method of making a metal core for alternating current applications by powder metallurgy is disclosed. Ferro-magnetic powder is pressed into a cross section of the core, with the thickness of the cross section approaching that below which the green density is no longer uniform throughout the volume of the part. Additional cross sections are pressed to meet the overall core thickness requirement when the sections are subsequently stacked. The sections are stacked in non contacting relationship and sintered. The sections are separated by an air gap or magnetic insulating medium.
    Type: Grant
    Filed: April 25, 1979
    Date of Patent: March 10, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventors: Orville W. Reen, Merlin L. Osborn
  • Patent number: 4245261
    Abstract: A digital displacement transducer to provide a digital output linear related to the displacement of a reference surface of an object. An eight track tape unit is coded with information related to displacements of 1/256 of an inch and applied to the reference surface. Means are then provided to assume the coded information of the tape unit; the means are of lesser coercivity than the tape unit. The information means is pulsed so that the information contained is the same, and a read out head is provided to read out which information was shifted, and thereby indicate the position of the reference surface of the object. A method is also provided to encode the information in the information means, switch the information therein, and obtain a read out.
    Type: Grant
    Filed: November 16, 1977
    Date of Patent: January 13, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventors: Jack W. Shilling, Jeffrey A. Dierker, Chester A. Mitchell
  • Patent number: 4244757
    Abstract: A process for producing electromagnetic silicon steel having a cube-on-edge orientation. The process includes the steps of: preparing a melt of silicon steel containing from 0.02 to 0.06% carbon, from 0.015 to 0.15% manganese, from 0.0006 to 0.0080% boron, up to 0.0045% nitrogen, from 0.005 to 0.019% sulfur, no more than 0.0065% phosphorus and from 2.5 to 4.0% silicon; casting the steel; hot rolling the steel; welding the steel to another steel member of like chemistry; cold rolling the steel to a thickness no greater than 0.020 inch; decarburizing the steel; applying a refractory oxide coating to the steel; and final texture annealing the steel.
    Type: Grant
    Filed: May 21, 1979
    Date of Patent: January 13, 1981
    Assignee: Allegheny Ludlum Steel Corporation
    Inventors: Frank A. Malagari, Jr., Richard P. Schrecongost
  • Patent number: 4238122
    Abstract: Individual charges of silicon steel are passed through a tunnel type furnace provided with charge and discharge vestibules. The annealing takes place in a hydrogen atmosphere and the vestibules are purged with nitrogen and then with hydrogen. The hydrogen used for purging is taken from the hydrogen in the annealing atmosphere and additional new hydrogen is added to the annealing atmosphere at the same time to maintain the pressure constant.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: December 9, 1980
    Assignee: Allegheny Ludlum Steel Corporation
    Inventors: Ralph E. Snyder, Philip R. Robinson
  • Patent number: 4236945
    Abstract: A phosphorus-iron powder is disclosed for use in the pressing and sintering of soft magnetic parts. This powder comprises a substantially phosphorous free iron powder blended with a sufficient quantity of ferrophosphorus powder having an average particle size of at least 10 micron and a phosphorus content of from 18 to 30%, to arrive at a phosphorus content for the mixture in a range of from about 0.40 to 1.25%. By pressing the blended mixture to a green density of at least 6.0 grams per cubic centimeter, and sintering the pressed mixture in a nonoxidizing atmosphere at a temperature of at least 1900.degree.F., the part linear shrinkage during sintering is less than 2%.
    Type: Grant
    Filed: November 27, 1978
    Date of Patent: December 2, 1980
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Orville W. Reen
  • Patent number: 4217150
    Abstract: A substantially non-porous, sulfuric acid resistant austenitic stainless steel and a method for making it are disclosed. The steel includes from 15-45% manganese, from 10-30% chromium, from 1-3% copper, from 0.85-3% nitrogen, from 0-2% silicon, from 0-1% carbon, and the balance iron and residuals. In addition to containing the foregoing elements within the above-noted composition ranges, the alloys must be such that: ##EQU1## The steels are cast and worked to avoid a dwell period in the temperature range 1000-1600.degree. F.
    Type: Grant
    Filed: January 26, 1979
    Date of Patent: August 12, 1980
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Albert G. Hartline, III
  • Patent number: 4217136
    Abstract: A substantially non-porous, austenitic stainless steel that is resistant to chloride pitting and sulfuric acid and a method for making it are disclosed. The steel includes from 21-45% manganese, from 10-30% chromium, from 0.85-3% nitrogen, from 0-1% carbon, from 0-2% silicon, and at least two elements selected from 1-3% copper, 1-4% nickel and 1-4% molybdenum with the combined weight of copper, nickel and molybdenum not exceeding 5% of the composition, and the balance iron and residuals, wherein the composition is such that: ##EQU1## The steel is cast and worked to avoid a dwell period in the temperature range of 1000.degree.-1600.degree. F.
    Type: Grant
    Filed: January 26, 1979
    Date of Patent: August 12, 1980
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Albert G. Hartline, III
  • Patent number: 4211042
    Abstract: A method is provided for treating the weld area of a welded ferritic stainless steel article to increase the resistance to intergranular corrosion. This method comprises the step of grinding the torch side surface of the welded article at a substantially uniform depth along the length of the weld after the material has solidified in the weld area, with the cross sectional dimension of the grind extending beyond the weld-base metal interface on both sides of the weld area. In accordance with this method, the depth of grind is uniformly controlled within the range of from at least 0.0005 inch as measured at the weld-base metal interface to less than 10% of the unground article thickness.
    Type: Grant
    Filed: December 22, 1978
    Date of Patent: July 8, 1980
    Assignee: Allegheny Ludlum Steel Corporation
    Inventor: Harry E. Deverell