COPPER-NICKEL-SILICON ALLOYS
A copper base alloy having an improved combination of yield strength and electrical conductivity consisting essentially of between about 1.0 and about 6.0 weight percent Ni, up to about 3.0 weight percent Co, between about 0.5 and about 2.0 weight percent Si, between about 0.01 and about 0.5 weight percent Mg, up to about 1.0 weight percent Cr, up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn, the balance being copper and impurities, the alloy processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 25% IACS.
1 . A copper base alloy having an improved combination of yield strength and electrical conductivity consisting essentially of:
between about 1.0 and about 6.0 weight percent Ni;
up to about 3.0 weight percent Co;
between about 0.5 and about 2.0 weight percent Si;
between about 0.01 and about 0.5 weight percent Mg;
up to about 1.0 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the alloy processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 25% IACS.
2 . The alloy according to claim 1 wherein the alloy has a conductivity of at least about 30% IACS.
3 . The alloy according to claim 1 wherein the alloy is processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 38% IACS.
4 . The alloy according to claim 1 wherein the alloy is processed to have a yield strength of at least about 143 ksi , and an electrical conductivity of at least about 37% IACS.
5 . The alloy according to claim 1 wherein the alloy is processed to have a yield strength of at least about 157 ksi, and an electrical conductivity of at least about 32% IACS.
6 . A copper base alloy having an improved combination of yield strength and formability consisting essentially of:
between about 1.0 and about 6.0 weight percent Ni;
up to about 3.0 weight percent Co;
between about 0.5 and about 2.0 weight percent Si;
between about 0.01 and about 0.5 weight percent Mg;
up to about 1.0 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the alloy processed to have a yield strength of at least about 137 ksi, and an mbr/t of less than 4 t for both good way bends and bad way bends.
7 . The copper base alloy according to claim 6 wherein the alloy has an mbr/t of less than about 2 t for both good way bends and bad way bends.
8 . The copper base alloy according to claim 6 wherein the alloy has an electrical conductivity of at least about 25% IACS.
9 . The copper base alloy according to claim 8 wherein the alloy has an electrical conductivity of at least about 30% IACS.
10 . A copper base alloy having an improved combination of yield strength, electrical conductivity, and formability, consisting essentially of:
between about 1.0 and about 6.0 weight percent Ni;
up to about 3.0 weight percent Co;
between about 0.5 and about 2.0 weight percent Si;
between about 0.01 and about 0.5 weight percent Mg;
up to about 1.0 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the ratio of (Ni+Co)/(Si−Cr/5) being between about 3 and about 7.
11 . The alloy according to claim 10 wherein the alloy is processed to have an mbr/t of less than about 4 t for both good way bends and bad way bends.
12 . The alloy according to claim 10 wherein the alloy is processed to have an mbr/t of less than about 2 t for both good way bends and bad way bends.
13 . The alloy according to claim 10 wherein the alloy is processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 38% IACS.
14 . The alloy according to claim 10 wherein the alloy is processed to have a yield strength of at least about 143 ksi , and an electrical conductivity of at least about 37% IACS.
15 . The alloy according to claim 10 wherein the alloy is processed to have a yield strength of at least about 157 ksi, and an electrical conductivity of at least about 32% IACS.
16 . The cooper base alloy according to claim 1 wherein the alloy is in the form of foil, wire, bar or tube.
17 . A copper base alloy having an improved combination of yield strength, electrical conductivity, and formability, consisting essentially of:
between about 3.0 and about 5.0 weight percent Ni;
up to about 2.0 weight percent Co;
between about 0.7 and about 1.5 weight percent Si;
between about 0.03 and about 0.25 weight percent Mg;
up to about 0.6 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the ratio of (Ni+Co)/(Si−Cr/5) being between about 3 and about 7.
18 . A copper base alloy having an improved combination of yield strength, electrical conductivity, and formability, consisting essentially of:
between about 3.0 and about 5.0 weight percent Ni;
up to about 2.0 weight percent Co;
between about 0.7 and about 1.5 weight percent Si;
between about 0.03 and about 0.25 weight percent Mg;
up to about 0.6 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the alloy processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 25% IACS.
19 . The alloy according to claim 18 wherein the alloy is processed to have a yield strength of at least about 137 ksi, and an electrical conductivity of at least about 38% IACS.
20 . The alloy according to claim 18 wherein the alloy is processed to have a yield strength of at least about 143 ksi, and an electrical conductivity of at least about 37% IACS.
21 . The alloy according to claim 18 wherein the alloy is processed to have a yield strength of at least about 157 ksi, and an electrical conductivity of at least about 32% IACS.
22 . A copper base alloy having an improved combination of yield strength, electrical conductivity, stress relaxation resistance, consisting essentially of:
between about 3.5 and about 3.9 weight percent Ni;
between about 0.8 and about 1.0 weight percent Co;
between about 1.0 and about 1.2 weight percent Si;
between about 0.05 and about 0.15 weight percent Mg;
up to about 0.1 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities, the alloy processed to have a yield strength of at least about 140 ksi, and an electrical conductivity of at least about 30% IACS.
23 . The alloy according to claim 22 wherein the ratio of (Ni+Co)/(Si−Cr/5) is between about 3.5 and about 5.0.
24 . The alloy according to claim 23 wherein the ration of Ni/Co is between about 3 and about 5.
25 . The alloy according to claim 22 wherein the ration of Ni/Co is between about 3 and about 5.
26 . A process for making a copper base alloy including nickel, silicon, cobalt and chromium, comprising:
melting and casting the alloy;
hot rolling from about 750° to about 1050° C.;
cold rolling to a convenient gauge for solutionizing;
solution annealing the alloy at between about 800° and about 1050° C. for from about 10 seconds to about one hour; and
subsequently quenching or rapidly cooling the alloy to ambient temperature to obtain an electrical conductivity of less than about 20% IACS (11.6 MS/m) and an equiaxed grain size of about 5-20 μm;
cold rolling the alloy for a 0 to about 75% reduction in thickness;
subjecting the alloy to an hardening anneal at about 300° to about 600° C. for about 10 minutes to about 10 hours;
subsequently cold rolling the alloy for an about 10 to about 75% reduction in thickness to finish gauge;
subjecting the alloy to a second age hardening anneal at 250 to about 500° C. for about 10 minutes to about 10 hours to achieve.
27 . The process according to claim 26 further comprising an intermediate recrystallization anneal after the hot rolling.
28 . The process according to claim 26 wherein the alloy consists essentially of between about 1.0 and about 6.0 weight percent Ni;
up to about 3.0 weight percent Co;
between about 0.5 and about 2.0 weight percent Si;
between about 0.01 and about 0.5 weight percent Mg;
up to about 1.0 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities.
29 . The process according to claim 28 wherein the alloy consists essentially of:
between about 3.0 and about 5.0 weight percent Ni;
up to about 2.0 weight percent Co;
between about 0.7 and about 1.5 weight percent Si;
between about 0.03 and about 0.25 weight percent Mg;
up to about 0.6 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn, the balance being copper and unavoidable impurities.
30 . The process according to claim 29 wherein the ratio of (Ni+Co)/(Si−Cr/5) being between about 3 and about 7.
31 . The process according to claim 29 wherein the alloy comprises between about 3.5 and about 3.9 weight percent Ni;
between about 0.8 and about 1.0 weight percent Co;
between about 1.0 and about 1.2 weight percent Si;
between about 0.05 and about 0.15 weight percent Mg;
up to about 0.1 weight percent Cr;
up to about 1.0 weight percent Sn, and up to about 1.0 weight percent Mn,
the balance being copper and impurities.