| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1469447 | Corrosion Science | 2012 | 11 Pages |
Four peak temperatures and two cooling rates were used in a Gleeble thermomechanical processing machine to simulate weld HAZ of API X-80 pipeline steel. Bainitic microstructures were observed at both 30 and 100 °C/s cooling rates. Bainite favoured higher passive current densities in alkaline solutions. The lowest peak temperature, 770 °C, produced the highest martensite-retained austenite (M–A) phase in the microstructure. Presence of M–A phases in the microstructure extended the passive region to higher potentials in alkaline solutions. Corrosion current density of the as-received sample was higher in acidic solutions and lower in alkaline solutions compared to the heat-treated ones.
► Corrosion of the heat affected zone of API-X80 pipeline steel was studied in both acidic and alkaline solutions. ► The correlation between the microstructure and corrosion behaviour of the samples was investigated. ► Presence of M–A phase in the microstructure enhanced the passivity of all samples in alkaline solutions.
