Description

Durability, performance and safety of a steel-belted tire are critically dependent on adhesion of the steel reinforcement to rubber. A bronze coating, having a nominal composition of 98.5 percent Cu with the balance Sn, is plated on tire bead wire to promote adhesion of the steel reinforcement to rubber. An oxide layer exists on the surface of the metallic coating. Properties of this oxide layer vary with thermal treatment time and temperature, and depend on the environmental conditions experienced by the coated bead wire. It is proposed that a critical amount of a specific oxide could significantly improve adhesion of steel to rubber.