Calculating Intermetallic Growth Rates to Set Stamping Tooling Replacement Intervals
Calculating dynamic intermetallic growth rates establishes press stroke limits that prevent tab burrs and optimize die replacement intervals.
Shear Zone Friction
Meaning
Tribological resistance occurring at the sliding interface between cutting tools and metal foils during the shearing process affects both wear and edge quality. In battery electrode cutting, shear zone friction determines the amount of heat and mechanical strain generated at the foil boundary. High friction leads to localized heating, which can melt polymeric binders or cause foil coating delamination.
Managing this tribological behavior is essential for ensuring clean, reliable electrode edges.
Tool Wear
Lubricants and coatings on cutting blades are used to reduce sliding resistance during high-speed production. In the absence of adequate lubrication, shear zone friction accelerates the adhesive wear of the punch and die faces. This rapid wear increases tooling costs and reduces the overall equipment effectiveness of the cell assembly line.
For this reason, tool steel surfaces are often polished or treated with diamond-like carbon coatings.
Edge Deformation
The force balance during shearing is strongly influenced by the resistance along the slipping boundaries. Higher shear zone friction results in greater plastic deformation of the electrode foil before the fracture phase begins. This plastic flow increases the height of metal burrs and leads to irregular edge profiles that exceed quality limits.
Sourcing engineers analyze this behavior when selecting materials for high-volume punch presses.
Thermal Effect
Heat generated by intense sliding contact can degrade the active material slurry near the cut line. This thermal stress degrades the binder polymer, which can lead to shedding of the active material during winding. Such loose material increases the risk of cell self-discharge and internal short circuits.