Microstructure and corrosion of AZ91 with small amounts of cerium
Research output: Contributions to collected editions/works › Article in conference proceedings › Research › peer-review
Authors
Recent investigations of magnesium-aluminum alloys revealed a strong influence of four key microstructural parameters on corrosion: porosity, volume fraction, distribution and Al-content of the γ-Al12Mg 17 phase. Additionally, an improved corrosion resistance was observed by the addition of rare earth elements. The influence of cerium on the casting skin, inner microstructure, and corrosion of sand-cast and die-cast AZ91D with 0.5-2.0 wt.% cerium was investigated by SEM before and after potentiodynamic measurements and electrochemical impedance spectroscopy in pH8 and pHll. Cerium significantly improved the corrosion resistance through formation of a passive layer. Strong influences of cerium on the microstructure (average grain size, changes in morphology and/or volume fraction of Mg17Al12 particles, and formation of cerium-rich intermetallic phases) were observed. Microstructural influences as well as the change in chemical composition alter the local corrosion mechanism and passive layer formation in AZ91D augmented with cerium.
| Original language | English |
|---|---|
| Title of host publication | Magnesium Technology 2010 - Held During TMS 2010 Annual Meeting and Exhibition |
| Editors | Sean R. Agnew, Neale R. Neelameggham, Eric A. Nyberg, Wim H. Sillekens |
| Number of pages | 5 |
| Publisher | John Wiley & Sons Inc. |
| Publication date | 2010 |
| Pages | 187-191 |
| ISBN (print) | 9780873397469 |
| Publication status | Published - 2010 |
| Externally published | Yes |
| Event | Magnesium Technology 2010 - TMS 2010 Annual Meeting and Exhibition - Seattle, WA, United States Duration: 14.02.2010 → 18.02.2010 |
- AZ91, Corrosion, Microstructure, Rare earth elements
- Engineering