| 摘要 |
PURPOSE:To obtain the material for the lead frame, cost thereof is cheap, plating property thereof is excellent and which has superior corrosion resistance and electrical conductivity, by adding Cr, Mo and Cu to a 5-20% Ni-Fe alloy. CONSTITUTION:Ni Has effects on corrosion resistance and electrical conductivity, and electrical conductivity is degraded when the quantity of Ni exceeds 20%, and corrosion resistance is remarkably degraded when the quantity is less than 5%. When a large quantity of C is made contain, not more than 0.1% C shall be made contain because a carbide is formed, causes the generation of corrosion and degrades corrosion resistance. The containing of Cr, Mo and Cu does not damage the adhesive property of plating and electrical conductivity and has a large effect on the improvement of corrosion resistance, but they have no effect on corrosion resistance when their quantities are less than 0.2% respectively while electrical conductivity and plating property are degraded when their quantities exceed 3.5%. More excellent corrosion resistance is obtained through the composite addition of Cr, Mo and Cu, but the effect is small when the total amount is less than 0.2% while the molding working electrical conductivity of the frame is remarkably degraded when it exceeds 3.5%. |
