Process for forming unusually strong joints between metals and ceramics by brazing at temperatures that do no exceed 750 degree C.

Patent · Wed Jan 01 04:00:00 EST 1986

OSTI ID:866047

Hammond, Joseph P ^[1]; David, Stan A ^[1]; Woodhouse, John J ^[2]

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1. Knoxville, TN
2. Crossville, TN

This invention is a process for joining metals to ceramics to form very strong bonds using low brazing temperature, i.e., less than 750.degree. C., and particularly for joining nodular cast iron to partially stabilized zirconia. The process provides that the ceramic be coated with an active metal, such as titanium, that can form an intermetallic with a low melting point brazing alloy such as 60Ag-30Cu-10Sn. The nodular cast iron is coated with a noncarbon containing metal, such as copper, to prevent carbon in the nodular cast iron from dissolving in the brazing alloy. These coated surfaces can be brazed together with the brazing alloy between at less than 750.degree. C. to form a very strong joint. An even stronger bond can be formed if a transition piece is used between the metal and ceramic. It is preferred for the transition piece to have a coefficient of thermal compatible with the coefficient of thermal expansion of the ceramic, such as titanium.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN
• DOE Contract Number: W-7405-ENG-26
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4621761
• OSTI ID: 866047
• Country of Publication: United States
• Language: English

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60ag-30cu-10sn
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