In:
Advanced Engineering Materials, Wiley, Vol. 24, No. 2 ( 2022-02)
Abstract:
Fe is a detrimental impurity element in secondary, i.e., recycled, Al–Si cast alloys for castability and mechanical properties. Fe removal can be achieved by binding Fe into Fe‐containing, primary particles and removing these from the, thus, Fe‐depleted Al–Si alloy melt. Expanding the application of filters beyond the removal of nonmetallic inclusions to increase the Fe‐removal efficiency can contribute to production of high‐quality, secondary Al–Si alloys. The usability of Al 2 O 3 , 3Al 2 O 3 · 2SiO 2 , MgAl 2 O 4 , Al 2 O 3 –C, and SiC filter materials in contact with Al7.1Si, Al7.1Si1.5Fe, and Al7.1Si0.75Fe0.75Mn alloys is evaluated in sessile‐drop and crucible experiments regarding wettability, chemical interaction, nucleation, particle formation, and the subsequent effect on the alloy composition. The Al–Si melts in contact with Al 2 O 3 act as nonreactive, low‐wetting reference systems. MgAl 2 O 4 and SiO 2 in 3Al 2 O 3 · 2SiO 2 are reduced, forming low‐wetting Al 2 O 3 , whereas Mg and Si enrich in the droplet. In contact with SiC and Al 2 O 3 –C, a thin layer of high‐wetting Al 4 C 3 is formed. In case of Al 2 O 3 –C, primary Fe‐containing particles are specifically attached to the Al 4 C 3 layer, which is associated with oriented growth of that layer. The remaining Fe content in the melt is 0.9 at% and beneficial kinetic effects for the Fe removal are suggested.
Type of Medium:
Online Resource
ISSN:
1438-1656
,
1527-2648
DOI:
10.1002/adem.202100595
Language:
English
Publisher:
Wiley
Publication Date:
2022
detail.hit.zdb_id:
2016980-2
detail.hit.zdb_id:
1496512-4
