Meaning
Welding regimes characterize the transfer of thermal energy through molecular vibration and diffusion within a solid or liquid. In conduction mode, the heat source intensity remains low enough to melt the surface without boiling the metal. This state is preferred for joining thin tabs to battery terminals where through-hole penetration is undesirable.
Process Stability
Thermal balance relies on the inherent conductivity of the material to distribute energy away from the focal point. Because conduction mode avoids the creation of a vapor cavity, the weld pool remains calm and free from splashing or spatter.
Penetration Depth
Joint thickness is restricted by the rate at which heat moves through the cross section of the part. Since the process depends on thermal diffusion, the conduction mode typically results in a shallow and wide weld bead. High power lasers can drive the melt front deeper but only by increasing the surface area exposed to the beam.
This limitation makes the technique suitable for foil stacking where precision is more vital than extreme depth. Thermal damage to sensitive internal components is minimized by the controlled nature of the heat input.
Energy Efficiency
Large portions of the applied power radiate away or dissipate into the bulk material without contributing to the fusion zone. Total energy consumption for conduction mode welding stays high relative to the volume of metal melted.
