| 摘要 |
PURPOSE:To provide a lead frame material with high working accuracy in final punching and a method for fabricating the same. CONSTITUTION:A lead frame material comprises Fe-Ni alloy or Fe-Ni-Co allay, wherein a rate of shrinkage of the material which has been heated at 650 deg.C for 10 minutes to original length of the material at normal temperature is 0.03% or less. A method for fabricating the lead frame comprises steps of working the material into a predetermined width after the material has been cold-drawn to product thickness and annealing for removing distortion, wherein annealing for removing distortion is done with no tension applied or annealing is done with tension suppressed to 5.0 kg/mm<2> or less, whereby rate of shrinkage of the material which has been heated at 650 deg.C for 10 minutes to the material at normal temperature is 0.03% or less. |
