Quantifying Carbide Banding Severity in Tool Steels for Cell Stamping Dies
Quantifying tool steel carbide banding via ASTM E1268 stereology prevents micro-chipping and premature fracture in high-takt battery cell stamping dies.
Punch Edge Chipping
Meaning
Cutting tool damage occurs when small fragments of metal break off from the sharp edges of a stamping punch. Punch edge chipping happens when the stress of punching through high-strength metals exceeds the fracture toughness of the tool steel. This damage ruins the clean shearing action of the press and leads to poor casing edges.
It is a common cause of unexpected tooling downtime. Sourcing high-quality tool steels with high toughness values is necessary to prevent these failures.
Wear Cause
Mechanical shock from repetitive metal-on-metal impacts creates micro-cracks along the cutting radius. The severity of punch edge chipping increases when forming harder aluminum or steel alloys. This cracking occurs more rapidly if the punch and die are misaligned.
Prevention Strategy
Correct steel selection focuses on alloys with high toughness and moderate wear resistance. To combat punch edge chipping, toolmakers use powdered metallurgy steels with refined carbide structures. These materials withstand higher impact forces than standard tool steels.
Quality Impact
Stamped battery casings show severe edge burrs and deformation when the punch suffers from broken edges. Sourcing departments monitor punch edge chipping to prevent the production of cans that fail weld checks or puncture the internal cell separator. The resulting quality checks ensure that the cell assembly is free from hazardous metal particles.