Accelerated atmospheric corrosion testing using a cyclic wet/dry exposure test; Galvanic couples of aluminum with graphite neoprene rubber, galvanized steel, and steel

Journal Article · Wed Nov 01 00:00:00 EST 1989 · Corrosion (Houston); (USA)

DOI:https://doi.org/10.5006/1.3585006· OSTI ID:6816010

Lyon, S B; Thompson, G E; Johnson, J E; Wood, G C ^[1]; Ferguson, J M ^[2]

---

1. Manchester Univ. (UK). Inst. of Science and Technology
2. Central Electricity Generating Board, Guildford (UK)

Aluminum corrosion is important in overhead electrical conductors constructed from aluminum wire centrally reinforced by galvanized steel strands. Inspection of conductor after long service has implicated rubber bushing material, on the outside, and the galvanized strands, on the inside, as providing potential galvanic sites for the initiation of rapid aluminum corrosion. Therefore, the galvanic corrosion of aluminum in contact with graphite-loaded neoprene rubber, hot-dip galvanized steel and steel was assessed in a cyclic wet/dry exposure test using mixed-salts spray solutions containing appropriate ratios of sulfate and chloride ion. Aluminum was found to corrode at between 3 to 6 times its uncoupled rate when associated with the rubber material. While the eta-phase, relatively pure Zn, galvanized layer remained intact, galvanic corrosion of aluminum was slow. However, on exposure of the zeta-phase, Zn/Fe intermetallic layer, aluminum corroded about 35 times faster than expected in a solution with a high level of Cl{sup -} ion. The importance of these data to conductor lifetime is discussed.

• OSTI ID: 6816010
• Journal Information: Corrosion (Houston); (USA), Vol. 45:11; ISSN 0010-9312
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
24 POWER TRANSMISSION AND DISTRIBUTION
ALUMINIUM
ELECTRIC CONDUCTORS
GRAPHITE
CORROSION
OVERHEAD POWER TRANSMISSION
MATERIALS TESTING
STEELS
ENVIRONMENTAL EFFECTS
INTERMETALLIC COMPOUNDS
IRON ALLOYS
NEOPRENE
PERFORMANCE TESTING
RUBBERS
ZINC ALLOYS
ALLOYS
CARBON
CHEMICAL REACTIONS
ELASTOMERS
ELEMENTAL MINERALS
ELEMENTS
IRON BASE ALLOYS
METALS
MINERALS
NONMETALS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
POLYMERS
POWER TRANSMISSION
TESTING
360105* - Metals & Alloys- Corrosion & Erosion
360604 - Materials- Corrosion
Erosion
& Degradation
240303 - Power Transmission Lines & Cables- Overhead Lines- (1990-)