The most important technical properties for leadframes are as follows:
- Electrical conductivity (which is proportional to the thermal conductivity)
- Yield strength Rp0.2 or, approximately, the Vickers Hardness HV which still allows the bending required for trimming and forming.
- Resistance to softening during mounting (die bonding)
Graph
The most significant materials for lead frames are plotted so as to show their electrical conductivity and a range of about 30 units of Vickers hardness HV. This range corresponds to the hardness which is most frequently specified for each alloy. Those materials which are particularly resistant to softening are denoted by *.
