| 摘要 |
A high strength lead frame material consists, by weight, of 0.5 to 22% Co, 22 to 32.5% Ni, not more than 1.0% Mn and not more than 0.5% Si and the balance Fe and incidental impurities. The contents of Ni and Co are selected so that the Ni content is 27 to 32.5% when the Co content is less than 12%, and so that, when the Co content is not less than 12%, the Ni content and the Co content meet the condition of 66%</= 2Ni+Co</=74%. The material has a two-phase structure formed of austenitic phase and martensitic phase, the austenitic phase occupying not less than 50% of the structure. |
