TY - GEN
T1 - Comparison of non-dendritic A380 alloy modified by Sr addition, high cooling rate and pouring in angular channel with rheocasting
AU - Hernández, Alfredo
AU - Chávez, J. Federico
N1 - Publisher Copyright:
© 2019 Author(s).
PY - 2019/7/2
Y1 - 2019/7/2
N2 - Die-casting is the most common processing of high performance components of aluminum alloys with Si as the predominant alloying element for a wide range of applications in the automotive and aeronautical industries. The Al-Si alloys with non-dendritic microstructure are gaining interest due to the improvement of mechanical properties by the spheroidal morphology and grain refinement of the microstructure replacing the dendritic arms produced by conventional casting. The A380 alloy added with 50 ppm of Sr poured at atmospheric conditions into a cooper mold with angular channel at 90° modifies the morphology in the primary solid, trimming the dendritic arms getting by this via, spheroidal grains of α(Al) phase surrounded by abundant eutectic structure. The solidification device with angular channel aids turbulent flow by stirring the alloy in the mushy state, at the same time as the thin wall of the mold increases the cooling rate, resulting in the decrease in grain size. Micrographs and mapping by SEM-EDS at the exit of the angular channel shows the modified shape of the α(Al) phase and fine eutectic structure all around, this last with the highest concentration of Si. Cu is located forming coarse precipitates outside from α(Al) and eutectic structure. A microstructural comparison in samples produced with this simplified and pressure less technic respect to rheocasting is presented.
AB - Die-casting is the most common processing of high performance components of aluminum alloys with Si as the predominant alloying element for a wide range of applications in the automotive and aeronautical industries. The Al-Si alloys with non-dendritic microstructure are gaining interest due to the improvement of mechanical properties by the spheroidal morphology and grain refinement of the microstructure replacing the dendritic arms produced by conventional casting. The A380 alloy added with 50 ppm of Sr poured at atmospheric conditions into a cooper mold with angular channel at 90° modifies the morphology in the primary solid, trimming the dendritic arms getting by this via, spheroidal grains of α(Al) phase surrounded by abundant eutectic structure. The solidification device with angular channel aids turbulent flow by stirring the alloy in the mushy state, at the same time as the thin wall of the mold increases the cooling rate, resulting in the decrease in grain size. Micrographs and mapping by SEM-EDS at the exit of the angular channel shows the modified shape of the α(Al) phase and fine eutectic structure all around, this last with the highest concentration of Si. Cu is located forming coarse precipitates outside from α(Al) and eutectic structure. A microstructural comparison in samples produced with this simplified and pressure less technic respect to rheocasting is presented.
UR - http://www.scopus.com/inward/record.url?scp=85068849282&partnerID=8YFLogxK
U2 - 10.1063/1.5112676
DO - 10.1063/1.5112676
M3 - Contribución a la conferencia
AN - SCOPUS:85068849282
T3 - AIP Conference Proceedings
BT - Proceedings of the 22nd International ESAFORM Conference on Material Forming, ESAFORM 2019
A2 - Arrazola, Pedro
A2 - Saenz de Argandona, Eneko
A2 - Otegi, Nagore
A2 - Mendiguren, Joseba
A2 - Saez de Buruaga, Mikel
A2 - Madariaga, Aitor
A2 - Galdos, Lander
PB - American Institute of Physics Inc.
T2 - 22nd International ESAFORM Conference on Material Forming, ESAFORM 2019
Y2 - 8 May 2019 through 10 May 2019
ER -
