Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C9/00—Alloys based on copper

Definitions

• Copper such as deoxidized electrolytic copper or oxygenfree high-conductivity (OFHC) copper and having an iron content in a near-trace (approximately 50 parts per million by weight) amount, possibly a chromium content to as much as l parts per million by weight, and other elements in amounts considered to be impurities, is alloyed with zirconium in the approximate range from 0.005 percent by weight to 0.03 percent by weight in combination with aluminum in a like or even greater amount.
• the resulting alloyed metal develops improved resistance to embrittlement at grain boundary regions, especially under conditions of approximately 900 F. to l,000 F. and 4,000 p.s.i. tensile stress to 5,000 psi. tensile stress.
• the amount of zirconium added be in the range of 0.005 to 0.03 percent by weight of the total alloy. In many instances the amount of zirconium alloyed into the copper to obtain the advantages associated with this invention is in the narrower range of approximately 0.01 to 0.02 percent by weight of the total alloy.
• the amount of aluminum to be alloyed into the same copper in the practice of this invention is essentially like the amount of zirconium although proportionally larger amounts of aluminum, within limits, do not appear to adversely affect the delay in onset of embrittlement that otherwise is obtained.
• the invention also preferably involves the addition of a corresponding amount of aluminum in the range of approximately from 0.005 to 0.03 percent by weight to the copper and often an amount in the range from 0.01 to 0.02 percent is utilized. No clear upper limit for the aluminum content is known and in at least one instance a total of 0.3 percent aluminum has been employed with a 0.02 percent zirconium addition.
• the alloying elements be combined with the copper in a controlled manner.
• the copper is vacuum melted, deoxidized by hydrogen bubbling in a partial vacuum, combined with the alloying elements under a vacuum condition, thoroughly mixed by argon bubbling in a partial vacuum, and afterwards also cast and solidified under vacuum.
• deoxidized copper is melted, alloyed, mixed, and cast and solidified entirely in a nonreactive gaseous environment such as in essentially pure argon. Exposure of the alloying elements to oxygen at metal-melting temperatures must be avoided.
• alloying conditions should be such that the zirconium and aluminum additions not be in an oxide, nitride, or carbide form or their effectiveness will not be realized. Accordingly, it is preferred that the specified alloying ingredients be combined in their metallic form. Although not presently known, it is conjectured that homologues of the alloying elements, particularly hafnium, are operative to obtain the advantages of the instant invention.
• Table 1 provides information regarding the improved alloys
• table II relates to coppers alloyed in a conventional manner. In each case, however, the alloyed metal tested was prepared in a manner involving deoxidation and was subjected in tensile bar form, to a tensile stress of at least 4,000 psi. and a temperature of approximately 950 F. The time to embrittlement (rupture) under the specified test conditions is given for each of the representative melt alloy compositions indicated.
• the method of alloying copper with the specified amounts of zirconium and aluminum is effective to significantly reduce the iron content of the copper.
• a starting copper having approximately 50 parts per million of iron by weight exhibited an iron content of 10 parts per million by weight (approximately) after the alloying with zirconium and aluminum had been completed.
• An improved copper alloy consisting on a weight basis of approximately from 0.005 to 0.03 percent zirconium, at least approximately from 0.005 to 0.03 percent aluminum, and the balance except for impurities deoxidized copper.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Conductive Materials (AREA)
• Manufacture And Refinement Of Metals (AREA)
• Manufacture Of Alloys Or Alloy Compounds (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=25370906

Family Applications (1)

Country Status (6)

Cited By (2)

Families Citing this family (3)

• 1969
  • 1969-11-18 US US877879A patent/US3615374A/en not_active Expired - Lifetime
• 1970
  • 1970-10-20 DE DE19702051493 patent/DE2051493B2/de not_active Withdrawn
  • 1970-10-27 CA CA096637A patent/CA924933A/en not_active Expired
  • 1970-11-11 GB GB5372670A patent/GB1332315A/en not_active Expired
  • 1970-11-16 FR FR7040987A patent/FR2069490A5/fr not_active Expired
  • 1970-11-17 JP JP45100782A patent/JPS5015210B1/ja active Pending

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