Lead-free solder compositions
A solder wire composition may include 85 to 95 weight percent bismuth, and at least 5 weight percent copper. The solder wire composition may have a diameter of less than about 1 millimeter, and an elongation at break of at least 20%.
1. A solder wire composition comprising:
about 85 to 95 weight percent bismuth; and
at least 5 weight percent copper,
wherein the solder wire has a diameter of less than about 1 millimeter, and
wherein the solder wire has an elongation at break of at least 20%.
2. The solder composition of claim 1 , comprising:
about 5 to 15 weight percent copper; and
about 0.01 to about 1 weight percent gallium.
3. The solder composition of claim 1 , comprising:
about 5 to 15 weight percent copper; and
about 0.01 to about 0.1 weight percent gallium.
4. The solder composition of claim 1 , comprising:
about 8 to 10 weight percent copper; and
about 0.01 to about 0.5 weight percent gallium.
5. The solder composition of claim 1 , comprising:
about 10 weight percent copper; and
about 0.1 weight percent gallium.
6. The solder composition of claim 1 , and further comprising:
less than about 0.1 weight percent lead.
7. The solder composition of claim 1 , and further comprising:
less than about 0.1 weight percent tin.
8. The solder composition of claim 1 , wherein the solder composition consists of bismuth, copper and less than 1 weight percent gallium.
9. The solder wire of claim 1 , wherein the solder wire has an elastic modulus of less than 15 GPa.
10. The solder wire of claim 1 , wherein the solder wire has a thermal conductivity greater than 10 W/m-K.