Preliminary Compatibility Assessment of Metallic Dispenser Materials for Service in Ethanol Fuel Blends

Intermediate Blends Infrastructure Materials Compatibility Study

“…Also consistent with previous results, 31 immersed coupons of cartridge brass, phosphor bronze, zincplated (galvanized) steel, and lead-plated (Terne) steel exhibited variable degrees of discoloration and minor corrosion product film formation. The highest corrosion rate observed was about 30 µm/year for the cartridge brass immersed in CE10a, and only one other material (bronze exposed to CE25a) exhibited a corrosion rate above 10 µm/year.…”

“…A report detailing the test protocol and metal analysis was published in 2010 by Pawel et al at the conclusion of this effort. 31 The elastomers that were investigated included eight fluorocarbon types provided by DuPont and 3M. The metals were evaluated for mass loss and surface analysis, while the elastomeric materials were evaluated for tensile properties, hardness, and swelling.…”

“…But it should be noted that none of the coupons suffered a measureable change in thickness and the original machining marks or plating grain structure remained visible on the coupon surface following testing. Further, based on earlier testing, 31 it is suspected that the corrosion rate of the copper-based materials decreases with extended exposure time.…”

“…These images indicate the degree of discoloration and film formation associated with each exposure (other materials indicated far less, or even no, discoloration and film formation). As indicated by the planned interval test results, 31 particularly for the copper-based alloys, these corrosion films form quickly upon exposure to fuel at elevated temperature and tend to be adherent to and protective of the substrate.…”

Compatibility Study for Plastic, Elastomeric, and Metallic Fueling Infrastructure Materials Exposed to Aggressive Formulations of Ethanol-blended Gasoline

“…Further, based on the initial testing, 12 it is suspected that the films formed on the copper-based alloys are quite protective and lead to corrosion rates that decrease with exposure time.…”