Study of Natural and Artificial Aging on AlSi9Cu3 Alloy at Different Ratios of Returnable Material in the Batch

Dana Bolibruchová; Marek Matejka; Alena Michalcová; Justyna Kasińska

doi:10.3390/ma13204538

Study of Natural and Artificial Aging on AlSi9Cu3 Alloy at Different Ratios of Returnable Material in the Batch

Materials (Basel). 2020 Oct 13;13(20):4538. doi: 10.3390/ma13204538.

Authors

Dana Bolibruchová¹, Marek Matejka¹, Alena Michalcová², Justyna Kasińska³

Affiliations

¹ Faculty of Mechanical Engineering, Department of Technological Engineering, University of Zilina, Univerzitná 8215/1, 010 26 Žilina, Slovakia.
² Department of Metals and Corrosion Engineering, University of Chemistry and Technology in Prague, Technická5, 166 28 Prague 6, Czech Republic.
³ Department of Metal Science and Materials Technology, Kielce University of Technology, Al. Tysiąclecia Państwa Polskiego 7, 25 314 Kielce, Poland.

Abstract

Aluminum alloys currently play an important role in the production of castings in various industries, where important requirements include low component weight, reduction of the environmental impact and, above all, reduction of production costs of castings. One way to achieve these goals is to use recycled aluminum alloys. The effect of natural and artificial aging of AlSi9Cu3 alloy with different ratios of returnable material in the batch was evaluated by a combination of optical, scanning, transmission microscope and mechanical tests. An increase in the returnable material in the batch above 70% resulted in failure to achieve the minimum value required by the standard for tensile strength and ductility. The application of artificial aging had a positive effect on the microstructure and thus on the mechanical properties of experimental alloys. By analyzing the results from TEM, it can be stated that in the given cases there is a reduced efficiency of θ'-Al₂Cu precipitate formation with an increase of the returnable material in the batch and in comparison with artificial aging, which is manifested by low mechanical properties.

Keywords: Al-Si-Cu secondary aluminum alloy; Cu precipitate; mechanical properties; natural and artificial aging; returnable material; transmission electron microscopy.