Materials database

Nickel-silicon precipitation-hardened copper alloy combining high strength (UTS ~700 MPa aged) with good electrical conductivity (35–45% IACS) and excellent stress relaxation resistance at elevated temperatures. Lead-free and RoHS compliant — the modern replacement for CuBe2 in many connector applications where beryllium toxicity is a concern. Trade names: Wieland K55 (Wieland), C70250 (Olin Brass). Used for automotive high-current connectors, IC lead frames, relay springs, fuse clips and miniaturized electronic contacts.