https://en.wikipedia.org/wiki/Beryllium_copper
also known as copper beryllium (CuBe ), beryllium bronze and spring copper
spring copper, could have thought of that one
High Electrical Conductivity
- The electrical conductivity of beryllium copper ranges from 16 to 65% IACS, depending on alloy and temper.
- Beryllium copper is the material of choice for high current density springs requiring low heat generation, due to the alloy’s combination of high electrical conductivity, thermal conductivity, and strength.
