Recycling Al-Si Alloy by Semisolid Material Dragged during Continuous-Casting Strip Processing

Abstract:

Recycled Al–Si (9.2%) alloy contaminated with Fe (0.3%), Pb (3.1%) and Sn (11.4 %) was cast and poured at 650 oC, approximately 50 oC above the liquidus line. A cooling slope was used to obtain a semisolid material that feeds a ceramic nozzle designed to function as a good contact area for solidification and improve the quality of strip casting. The internally cooled material rolls in soluble oil (1 oil / 9 water) at a rate of 0.2 l/s and works as a heat exchanger which drags the metallic slurry puddle generated at the roll surface at a speed of 0.12 m/s. This forms a metallic strip with a thickness of 2 mm and a width varying from approximately 45 mm to 60 mm. The cooling system of the rolls, combined with four springs placed at the housing screw, prevented adhering of the metallic strip during production at a pressure of approximately 450 N. Cracks were observed on the strip surfaces; however, these defects did not interrupt the continuous flow of the solidified strip during manufacturing. The strip’s poor surface quality could be related to the Pb and Sn contamination as well as cold cracks due to the low pouring temperature. Al-Si eutectics positioned at a grain boundary of α-Al globular structures, as well as the presence of a Sn phase, resulted in a metallic strip with a yield stress, maximum stress and elongation of 94.5 MPa, 100.2 MPa and 1.6%, respectively.

• Periodical: Solid State Phenomena (Volume 327)
• Pages: 293-299
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.327.293
• Online since: January 2022
• Authors: Antonio de Pádua Lima Filho*, Lucas Veronez Goulart Ferreira, Pedro Barbosa de Oliveira Neto, Fabian Hoisand, Rodrigo Alessandro Nunes de Oliveira, Wyser José Yamakami, Marcio Antonio Bazani, Miguel Borodiak
• Keywords: Rapid Solidification, Recycling of Al-Si Alloys, Rheorolling

References

[1] R. D. Pehlke, Continuous casting, in: American Society Materials – ASM handbook, Casting, ninth ed., The Materials Information Society, New York, 1978, pp.309-316.

[2] H. Bessemer, On the manufacture of continuous sheets of malleable iron and steel, direct from the fluid metal. Journal of the Iron and Steel Institute, [s.l.], 1891.

[3] R. W. Hazelett, The present status of continuous casting between two moving belts. AISE Year Book, U.S, v.43, pp.105-110, June (1966).

[4] HAZELETT. Continuous Innovation. 2020. Information on https://www.hazelett.com/.

[5] F. Fisher jr., M. Schueren, P. Campbell, W. Blejde, R. Mahapatra, The Castrip Process: Commercialized Thin Strip Casting of Steel, in: Proc. METEC Congress, Düsseldorf, 2007, pp.1-8.

[6] T. Haga, Semi-solid roll casting of aluminum alloy strip by melt drag twin roll caster, Journal of Materials Processing Technology 111 (2001) 64-68.

DOI: 10.1016/s0924-0136(01)00498-8

[7] T. Haga, S. Suzuki, Study on high-speed twin-roll caster for aluminum alloys, Journal of Materials Processing Technology 143-144 (2003) 895-900.

DOI: 10.1016/s0924-0136(03)00400-x

[8] G. Li, B. G. Thomas, Transient thermal model of the continuous single-wheel thin-strip casting process, Metallurgical and Materials Transactions B 27B (1996) 509-525.

DOI: 10.1007/bf02914916

[9] A. D. P. Lima Filho, L. V. G. Ferreira, P. B. D. Oliveira Neto, C. B. D. Oliveira, C. H. D. O. Arantes, T. P. D. Castro, M. Borodiak, A. L. Quadro, Influence of pouring temperature and alloy additions on the quality of a semisolid material dragged during the continuous-casting strip processing of Al-Si A413, Solid State Phenomena 285 (2019) 224-233.

DOI: 10.4028/www.scientific.net/ssp.285.224

[10] P. Y. Menet, F. Basson, K. Maiwald, R. Cayol, M. Bosh. Strip casting technology: a key to product quality, in: Proceedings of the International Melt Quality Workshop, Madrid, pp.1-5, (2001).

[11] Companhia Brasileira de Alumínio – CBA. Produtos Transformados, São Paulo, 2017. Information on http://www.aluminiocba.com.br/produtos/transformados.

[12] H. Harada, H. Nakamura, T. Haga, H. Watari. Casting of Al-25%Si alloy strip by a vertical type twin roll caster, The Japan Society of Mechanical Engineers (2011) 1074-1077.

DOI: 10.1299/kikaia.77.1074

[13] M. Kim, S. Kumai, Solidification structure and casting defects in high-speed twin-roll cast Al-2 mass% Si alloy strip, Materials Transactions, 54 (2013) 1930-1937.

DOI: 10.2320/matertrans.l-m2013824

[14] A. D. P. Lima Filho, M. I. Yamasaki, L. A. Ono, L. Nampo, A. Padilha, A comparison of deep drawing and ironing of metal alloy strip produced conventionally and non-conventionally via semi solid material processing, Solid State Phenomena 141-143 (2008) 49-54.

DOI: 10.4028/www.scientific.net/ssp.141-143.49