About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Cast Shop Technology
|
Presentation Title |
Control Pin Refractory Reaction in High Magnesium Aluminium-melts |
Author(s) |
Reiza Mukhlis, John F Grandfield, M. Akbar Rhamdhani |
On-Site Speaker (Planned) |
Reiza Mukhlis |
Abstract Scope |
Through 2019, pin hole defects were observed in can end 5182 Al sheets produced at Hulamin. Initial SEM examination revealed the presence of Al-Mg-O spinels inclusions with silica traces. The lack of calcium and phosphorous in the inclusions suggested that fused-silica pins and downspouts reacted with magnesium in the melt. The authors have carried out a systematic study to investigate the mechanism further which included pin-immersions tests, thermodynamic analysis, and SEM examinations. The thermodynamic analysis, confirmed in the immersion test, showed that at low magnesium content MgO forms as the reaction product but at higher magnesium levels AlMgO4 forms. It seems likely that the reaction products take up more volume which would cause further spalling of the fused-silica and BN-coating. The importance of examining and maintaining the integrity of the BN-coating was highlighted to prevent melt-to-pins reaction. It is speculated that lower porosity pins would be more resistant to attack. |
Proceedings Inclusion? |
Planned: Light Metals |
Keywords |
Magnesium, Pyrometallurgy, Other |