Issue 42

M. Tocci et alii, Frattura ed Integrità Strutturale, 42 (2017) 337-351; DOI: 10.3221/IGF-ESIS.42.35 337 Investigation of mechanical properties of AlSi3Cr alloy Marialaura Tocci, Annalisa Pola, Lorenzo Montesano , G. Marina La Vecchia Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123, Brescia, Italy m.tocci@unibs.it , http://orcid.org/0000-0002-7515-0615 annalisa.pola@unibs.it , http://orcid.org/0000-0002-0722-6518 lorenzo.montasano@unibs.it , http://orcid.org/0000-0001-5465-6265 marina.lavecchia@unibs.it, http://orcid.org/0000-0001-5919-0396 Mattia Merlin, Gian Luca Garagnani Department of Engineering (DE), University of Ferrara, Via Saragat 1, 44122, Ferrara, Italy mattia.merlin@unife.it, http://orcid.org/0000-0003-4685-1073 gian.luca.garagnani@unife.it , http://orcid.org/0000-0002-5403-0868 A BSTRACT . In the present paper, microstructural and mechanical properties of an innovative AlSi3Mg alloy were studied. Particularly, the effect of the addition of Cr and Mn on tensile strength and impact toughness was evaluated. In fact, the presence of these elements leads to the formation of an intermetallic phase with a globular or polyhedral morphology. It was therefore investigated the role played by Cr-Mn containing particles in the failure mechanism and the influence of the heat treatment parameters. Moreover, tensile and impact tests were performed on A356 samples in T6 condition, whose results were compared with the performance of the innovative alloy. Considering the static properties, the innovative alloy showed remarkable values of tensile strength, while ductility was improved only after heat treatment optimization. Poor impact toughness values were measured and the microstructural analysis confirmed the presence of coarse intermetallics, acting as crack initiation and propagation particles, on the fracture surfaces. K EYWORDS . Al-Si-Mg alloys; Tensile test; Impact test; Fracture surface. Citation: Tocci, M., Pola, A., Montesano, L., La Vecchia, G.M., Merlin, M., Garagnani, G.L.., Investigation of mechanical properties of AlSi3Cr alloy, Frattura ed Integrità Strutturale, 42 (2017) 337-351. Received: 11.08.2017 Accepted: 11.09.2017 Published: 01.10.2017 Copyright: © 2017 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION n the last decades, the light weighting of cars and trucks has become a very widely discussed theme [1] in both academic and industrial world. The design of more efficient processes and the development of stronger and lighter materials enhance the reduction of weight of cars and trucks components, allowing the decrease of fuel consumption and toxic emissions in atmosphere. For such reasons, the use of aluminum alloys in transports is increasing in the last years. Among Al alloys, Al-Si-Mg alloys are the most used for automotive castings production [2,3] because of their excellent castability, good corrosion resistance, high elongation and significant strength. I