Effect of Low-Levels of Strontium on the Oxidation Behavior of Selected Molten Aluminum–Magnesium Alloys

Özdemir, Ö.; Gruzleski, J. E.; Drew, R. A. L.

doi:10.1007/s11085-009-9158-x

Cited by 18 publications

(13 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous studies on the effects of Sr on the oxidation have shown mixed results with its effectiveness for inhibiting oxidation. [13,14] Rare earth elements stand out as a potential alternative as they are surface active and will readily react. Yttrium has seen usage as an alloying element to reduce the oxidation of solid Mg alloys at 500°C and may prove effective in controlling the oxidation of liquid AlMg alloys.…”

Section: Discussionmentioning

confidence: 99%

The Mechanism Behind the Oxidation Protection of High Mg Al Alloys with Beryllium

Smith

Kvithyld

Tranell

2018

Metall Mater Trans B

View full text Add to dashboard Cite

The addition of beryllium to Al-Mg alloys is known to cause a dramatic decrease in oxidation; however, the mechanism behind this protective effect is not yet fully understood. To aid in finding an alternative to the toxic Be, a fundamental study of Be additions has been carried out. Industrial samples containing 2 ppm Be and a model alloy with 100 ppm Be were oxidized at temperatures between 550°C and 750°C in a horizontal tube furnace. The oxide layer and oxide-metal interface were investigated using SEM, FIB, and XPS. It was found that Be forms a uniform oxide layer at the oxide-metal interface which slows the diffusion of Mg and Al from the metal into the oxide layer resulting in a reduced oxidation rate and an increase in the time for breakaway oxidation to occur.

show abstract

Section: Discussionmentioning

confidence: 99%

The Mechanism Behind the Oxidation Protection of High Mg Al Alloys with Beryllium

Smith

Kvithyld

Tranell

2018

Metall Mater Trans B

View full text Add to dashboard Cite

show abstract

“…Previous studies found that alloying with strontium (Sr) decreased the oxidation rate of Al alloys [176,177]. Aydin and co-workers [178] studied the oxidation behaviour of Mg-2.5 wt.% Sr and Mg-6 wt.% Sr alloys in the solid state at 500 C.…”

Section: Srmentioning

confidence: 99%

Oxidation of magnesium alloys at elevated temperatures in air: A review

et al. 2016

View full text Add to dashboard Cite

Highlights The oxidation behaviours of Mg alloys from low to high temperatures are reviewed. Characteristics of MgO during oxidation is discussed. Mechanisms of Mg oxidation is presented. Effect of various alloying elements is analysed. AbstractThis paper reviews (i) the oxidation of Mg alloys at elevated temperatures in air; (ii) the influence of alloying elements on the oxidation of Mg alloys; and (iii) the progress in the development of oxidation-resistant Mg alloys. Low oxidation rates have been shown by Mg alloys containing the alloying elements, Ca, Be and rare earth elements. However, these alloying elements may also decrease mechanical properties, such as ductility.

show abstract

“…In 2004, Pekguleryuz and Vermette [14] compared the amount of oxide formed on commercial AZ91D containing 9 ppm Be with the AZ91E (<0.001 wt% Be þ 75 ppm Sr) alloy. The weight gain measurements showed that similar amounts of oxides formed on each alloy and that Be could be replaced by Ozdemir et al [15] showed that the surface activity of Sr in Al-Mg alloys decreases the oxidation rate by suppressing spinel crystal formation and forming a Sr-enriched region that acts as a barrier to inward oxygen diffusion. Aydin et al [16] found that the T i of pure Mg increased from 640 to 860°C with the addition of 6 wt% Sr.…”

Section: Introductionmentioning

confidence: 97%

High Temperature Oxidation Behavior of Hypoeutectic Mg–Sr Binary Alloys: The Role of the Two‐Phase Microstructure and the Surface Activity of Sr

2014

View full text Add to dashboard Cite

The high temperature oxidation behavior of Mg-Sr hypoeutectic alloys was investigated. The oxide layer was characterized after isothermal heating experiments that were conducted at 500°C in dry airflow for 12 h. It was seen that a non-uniform oxide scale formed on hypoeutectic Mg-Sr alloys with a two-phase structure whereby the oxide over the interdendritic intermetallic phase had a finer grain size than the oxide over the a-Mg dendrites. The interrupted tests on selected alloys showed that the two phases exhibit different oxidation sequences of Sr and Mg. It was observed that the intermetallic phase oxidizes first with the formation of both MgO and SrO on the surface. The oxidation proceeds with SrO and MgO formation on the a-Mg. This sequence is different from what is predicted as possible via thermodynamic calculations based on the activities of the elements on the two-phases. SEM/EDS analyses revealed that the Sr surface-enrichment has occurred, which explains the differences between the observation and the assessment. Thermodynamic re-assessment suggested that the Sr enrichment on the surface due to the surface activity of Sr in Mg could largely determine the initial oxidation sequence.

show abstract

Effect of Low-Levels of Strontium on the Oxidation Behavior of Selected Molten Aluminum–Magnesium Alloys

Cited by 18 publications

References 15 publications

The Mechanism Behind the Oxidation Protection of High Mg Al Alloys with Beryllium

The Mechanism Behind the Oxidation Protection of High Mg Al Alloys with Beryllium

Oxidation of magnesium alloys at elevated temperatures in air: A review

High Temperature Oxidation Behavior of Hypoeutectic Mg–Sr Binary Alloys: The Role of the Two‐Phase Microstructure and the Surface Activity of Sr

Contact Info

Product

Resources

About