Corrosion Damage to a Dropped Handlebar Made of AA7075

Abstract

Abstract Damage by corrosion was discovered on a dropped handlebar made of AA7075 during an inspection at a workshop. The possible causes are presented and the corrosion types encountered are interpreted. Stress corrosion or corrosion fatigue under the effect of chloride can be concluded from the damage pattern and reconstructed conditions of use. The heterogeneous microstructure containing a large number of intermetallic precipitates accelerates the start of corrosion because microgalvanic elements are formed. Although aluminium alloys, when in an urban environment, do not exhibit a pronounced tendency to corrosion the conditions of corrosion can locally change in use to such an extent that corrosion damage will occur. In the present case, a remedy can primarily consist in inspections at well-adapted intervals and the exchange of the handlebar tape in good time.