LONG-TERM-DURABILITY OF ALUMINIUM-EPOXY-JOINTS: DEPENDENCIES BETWEEN SURFACE PRE-TREATMENT AND AGEING MECHANISMS

摘要

Neither good corrosion resistance nor "clean" (i.e. chemically active) surfaces seems to be responsible for a good durability of bonded aluminium-epoxy-joints exclusively. There are hints for a significant influence of very thin, filigree oxide structures onto long-term durability, especially in corrosion-vests. These oxide-layers are at least three times smaller than anodised oxide-layers, showing in a state without adhesive poor corrosion resistance and a high degree of organic contamination partly. Nevertheless those "nano-morphologies" are adequate to generate an oxide / polymer ― barrier zone, which decreases the kinetics of bondline-corrosion in a significant manner.