| 摘要 |
PURPOSE:To obtain the lead frame material having excellent corrosion resistance and plating property. CONSTITUTION:The material consists of an alloy in which either one or two kinds of Cu or Ni are made contain by 1-17% (where Cu is limited to 5% or Ni to 15%) as the total sum in case of two kinds and the remainder is Fe substantially. When Cu exceeds 5%, the hot workability of the material is degraded, cracks are easy to be generated on forging and blooming rolling, and there is difficulties in the manufacture of a board material. When Ni exceeds 15% and Ni+Cu exceed 17%, the transformation of austenite ferrite is generated at a comparatively low temperature (such as 300 deg.C or less), and transformation is often generated in the lead frame material due to heating (a forming temperature of plastic) in case of the assembly of a device. When the transformation has an effect on the deformation of a punched product, the dimension accuracy of the lead frame is degraded, and the lead frame cannot be assembled automatically. |
