Tool Steel Metallurgy Fundamentals for High Volume Battery Component Manufacturing Dies
Powder metallurgy tool steels with cryogenic phase stabilization eliminate edge chipping and cut amortized tooling costs by over eighty percent in battery dies.
Adhesive Galling
Meaning
Surface damage mechanisms occurring during sliding contact between metal parts under heavy loads represent a major failure mode in stamping and forming dies. Adhesive galling begins with localized friction that disrupts protective oxide layers on the contacting metal surfaces. The resulting direct metal-to-metal contact causes microscopic welds to form and shear repeatedly, tearing material from one surface and depositing it on the other.
This progressive wear occurs primarily in the absence of adequate lubrication or when the load exceeds the film strength of the lubricant.
Metal Transfer
High contact pressures and friction generate localized heat that accelerates the welding process. During adhesive galling, transferring material builds up on the punch or die, creating hardened protrusions that scratch subsequent workpieces.
Prevention Method
Applying hard physical vapor deposition coatings to the sheet-metal forming tools provides an effective barrier against surface welding. Lubricants containing extreme-pressure additives further reduce the likelihood of adhesive galling by maintaining a protective barrier under heavy loads.
Mechanical Consequence
Scratches and tearing caused by built-up material degrade the cosmetic and structural quality of the formed battery cans. Once adhesive galling initiates, the friction force increases dramatically, which elevates the risk of tool breakage and forces immediate line stoppage for polishing.