The Transfer Film Mechanism
Solid lubricant (PTFE, graphite, or MoS₂) is embedded in pockets throughout the bronze matrix. During sliding, microscopic heat at contact points softens the lubricant, which transfers to the leader pin surface. This creates a thin dry film (< 1 µm) that reduces friction from 0.30 (dry metal) to 0.05-0.15 (lubricated).