Method of manufacture

• US 3,019,513 A
• Filed: 05/22/1958
• Issued: 02/06/1962
• Est. Priority Date: 05/22/1958
• Status: Expired due to Term

• Current Assignee: Charles W. Vigor, Clarence J. Tobin, James C. Holzwarth, James R. Hornaday Jr
• Original Assignee: Charles W. Vigor, Clarence J. Tobin, James C. Holzwarth, James R. Hornaday Jr
• Inventors: Hornaday, James R. Jr., Vigor, Charles W., Tobin, Clarence J., Holzwarth, James C.
• Application Number:
  US03/737,000
• Time in Patent Office: 1,356 Days
• US Class Current: 228/116
• CPC Class Codes: B21D 53/045 by inflating partially united plates
• CPC Class Codes: Y10S 428/939 Molten or fused coating
• CPC Class Codes: Y10T 29/4935 Heat exchanger or boiler making
• CPC Class Codes: Y10T 428/12965 Both containing 0.01-1.7% carbon [i.e., steel]

Claims

7. IN A PROCESS FOR MANUFACTURING A STAINLESS STEEL ARTICLE HAVING INTEGRAL PASSAGES THEREIN, SAID STAINLESS STEEL HAVING A NOMINAL COMPOSITION OF ABOUT 16% TO 18% CHROMIUM, ABOUT 10% TO 14% NICKEL, ABOUT 2% TO 3% MOLYBDENUM, ABOUT 1% MAXIMUM CARBON, ABOUT 2% MAXIMUM MANAGANESE, ABOUT 1% MAXIMUM SILICON AND THE BALANCE SUBSTANTIALLY IRON, THE STEPS COMPRISING PROVIDING AT LEAST TWO SAID STAINLESS STEEL PLATES, CLEANING THE PLATE SURFACES, APPLYING A STOP-WELD MATERIAL OVER PORTIONS. WHICH ARE NOT TO BE BONDED OF ONE OF SAID PLATES, SUPERIMPOSING THE OTHER PLATE OVER THE FIRST-MENTIONES PLATE WHEREBY THE STOP-WELD MATERIAL IS SANDWICHED BETWEEN SAID PLATES, BRIGHT ANNEALING THE ASSEMBLED PLATES IN A DRY PURIFIED HYDROGEN ATMOSPHERE AT A TEMPERATURE RANGING FROM ABOUT 1800* F. TO 2100* F. FOR A PERIOD OF TIME SUFFICIENT TO THOROUGHLY SOFTEN THE SHEETS AND REMOVE THE OXIDES THEREON, COLD ROLLING THE SHEETS TO AT LEAST A 50% REDUCTION IN CROSS SECTION, SUBJECTING THE ASSEMBLY TO A SECOND BRIGHT ANNEALING OPERATION IN A DRY PURIFIED HYDROGEN ATMOSPHERE WITHIN A TEMPERATURE RANGE OF 1800* F. TO 2100* F. FOR A TIME SUFFICIENT TO STRESS RELIEVE THE STRUCTURE AND PROMOTE DIFFUSION BONDING BETWEEN THE PLATES, THEN SUBJECTING THE ASSEMBLY TO A SECOND COLD ROLLING OPERATION INVOLVING AT LEAST A 30% REDUCTION IN CROSS SECTION BASED ON A THICKNESS OF THE ASSEMBLY RESULTING FROM THE FIRST COLD ROLLING OPERATION, THEN AGAIN ANNEALING THE STRUCTURE IN A DRY PURIFIED HYDROGEN ATMOSPHERE WITHIN A TEMPERATURE RANGE OF 1800* F. TO 2100* F. FOR A TIME SUFFICIENT TO STRESS RELEIVE THE STRUCTURE AND PROMOTE DIFFUSION BONDING AND HOMOGENEITY OF THE STRUCTURE THROUGHOUT THE PORTIONS OF THE CROSS SCETION OF THE ASSEMBLY WHICH ARE BONDED, AND THEN SUBJECTING THE PORTIONS OF THE STRUCTURE WHICH ARE NOT TO BE BONDED TO HYDRAULIC PRESSURE, WHEREBY THESE PORTIONS ARE EXPANDED TO FORM PASSAGES.