Resistance Welding Dissimilar Steels With a High-Resistivity Interlayer

A third material with intermediate electrical resistivity is introduced between the high-resistivity and low-resistivity steel work-pieces. This intermediary material acts as a thermal bridge, conducting heat from the high-resistivity side to the low-resistivity side, thereby enabling adequate weld penetration into both materials while maintaining the ability to join dissimilar materials.

The electrical resistivity parameter of the joining system is modified by introducing a third material with specific resistivity characteristics. This changes the heat generation and distribution parameters during resistance welding, allowing thermal energy to be properly distributed to achieve penetration into both high and low resistivity steels simultaneously.

The third material serves multiple functions simultaneously: it acts as an electrical resistor to generate heat, a thermal conductor to transfer heat to the low-resistivity steel, and a bonding interface for weld formation. This multi-functionality justifies the addition of the material by providing several critical functions in one component.

The joining system becomes a composite structure involving three different materials with complementary properties. The composite nature allows each material to contribute its specific characteristics (electrical resistivity, thermal conductivity, mechanical strength) to achieve overall welding success that none of the individual materials could provide alone.