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US4777822A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of hot rolling copper

Assignee: Sumitomo Electric Industries Ltd
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Filing: 1987-12-03
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Granted: 1988-10-18
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Expires: 2007-12-03
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Abstract

Abstract The present invention relates to a method of hot rolling copper or copper alloys such as copper wires and coppr plates. The present invention has succeeded in remarkably prolonging useful life of the tools used for hot rolling, and improving the surface quality of the rolled products by replacing the conventional methods of hot rolling copper using tools made of cemented carbide, die steel, high-speed steel, etc. by a method using tolls made essentially of Si3N4. Si3N4 tools used in the present invention contain at least one kind of sintering aid selected from the group consisting of Al2O3, AlN, MgO, Y2O3 and ZrO2, have a sintering density of 90% or more, Rockwell hardness of 88 or more and an average particle diameter of 2 mu or less, and contain beta -type Si3N4 as a main ingredient.

Inventors

  • 👤 Ikuji Uemura
  • 👤 Fumio Ono
  • 👤 Eiji Kamijo
  • 👤 Tatsuya Nishimoto
  • 👤 Matsuo Higuchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 10:52
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/597; C04B35/584

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 102 words
A method of hot rolling copper or a copper alloy, which comprises hot rolling the copper or copper alloy using a deformation tool consisting essentially of β-type Si 3 N 4 in an amount of 60% by weight or more and at least one sintering aid selected from the group consisting of Al 2 O 3 , AlN, MgO, Y 2 O 3 and ZrO 2 in an amount of 0.1 to 40% by weight, said tool having a sintering density of 90% or more, a Rockwell hardness of 88 or more and an average particle diameter of 2 microns or less.
Claim 2
Independent Claim 102 words
A method of hot rolling copper or a copper alloy, which comprises hot rolling the copper or copper alloy using a deformation tool consisting essentially of β-type Si 3 N 4 in an amount of 60% by weight or more and at least one sintering aid selected from the group consisting of Al 2 O 3 , AlN, MgO, Y 2 O 3 and ZrO 2 in an amount of 0.1 to 40% by weight, said tool having a sintering density of 90% or more, a Rockwell hardness of 88 or more and an average particle diameter of 2 microns or less.
Claim 3
Dependent Claim 27 words
A method as set forth in claim 1, wherein said tool has a sintering density of 97% or more and a Rockwell hardness of 90 or more.

References Cited (Backward Citations)

DE2536354A1 Cited
US4264547A Cited
US4412009A Cited
JPH109519A Cited
JPH112135A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-10-18 1992-04-18 1992-10-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-10-18 1996-04-18 1996-10-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-10-18 2000-04-18 2000-10-18 $7700.00 Window Closed / Lapsed

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