Development of a new methodology to use recycled Secondary Aluminum substituting primary A356 aluminum alloy in safety components in low pressure technology E. Ochoa de Zabalegui EDERTEK S. Coop., Mondragon, Spain J. Huarte, E. Zoco, J. Arraiza, MAPSA S. Coop., Orcoyen, Spain E. Rivero, A. Rios, Fagor Ederlan S. Coop., Eskoriatza, Spain I. Anza; I. Alfaro, F. Sáenz de Tejada, BEFESA Aluminio Bilbao S. L., Erandio, Spain I. Hurtado, Z. Azpilgain, G. Arruebarrena, Mondragon Unibertsitatea, Mondragon, Spain J. Arriaran, I. Landa, P. Rodríguez, EDERTEK S. Coop., Mondragon, Spain |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Copyright 2014 World Foundry Organization ABSTRACT FAGOR EDERLAN and MAPSA members of Fagor Ederlan Chassis & Powertrain Division manufacture safety components such as knuckles, control arms, and wheels using primary aluminum alloy, named A356 or AlSi7Mg0,3. Components finally are heat Treated by a T6 or T64 reaching final properties. The goal of using a secondary aluminum source is been stopped due to poor properties of such alloys where contamination by elements such as Fe and Cu promotes the formation of non-desirable phases at the microstructure and therefore, reducing considerably the mechanical properties and corrosion behavior. A project has been carried out where two neutralizer compositions have been developed, avoiding the no desired Fe rich needle-shaped phases (β-Al5FeSi). Adding these neutralizing alloys it is possible to ensure the mechanical properties and functional behavior of security parts using a secondary A356 alloy containing 0,4 % of Fe. A cost study was also carried out to compare the use of primary or secondary aluminum alloy, in order to make economical efficient the whole process. INTRODUCTION FAGOR EDERLAN and MAPSA, members of Fagor Ederlan Chassis & Powertrain Division, manufacture safety components such as knuckles, control arms and wheels by low pressure technology. The automotive industry compels to use only primary alloys for this kind or casting parts, in order to avoid mechanical properties and corrosion resistance reduction by Fe and Cu contaminations respectively. The used primary alloy is named A356 or AlSi7Mg0,3 with Fe and Cu content limitations (Table 1). Components finally are heat treated by a T6 or T64 reaching final properties (Table 2). Table 1. Chemical composition with internal limitations of the A356 alloy (in wt %) Si Cu Mg Mn Fe Zn 6,5-7,5 <0,05 0,25-0,4 0,05 <0,18 <0,07 Table 2. Heat treatment (T6) parameter employed by Fagor Ederlan Temp time Annealing 540 C 1004 F 8 h Quenching 30-60 C 86-140 F 10 min Aging 160 C 320 F 6 h On 2009 primary aluminum alloys was much more expensive than secondary alloys, therefore this project was started in order to increase the material sources for the foundries. The principal objective of the project was to neutralize the negative effect of high contents of Fe in the mechanical characteristics, by adding neutralized elements in order to be able to produce security parts by secondary aluminum alloys. STATE OF THE ART High Fe contents on Al-Si alloys leads in the formation of different intermetallic phases (Table 3), been the β- Al 5 FeSi, because of his needle shape, the most detrimental for the mechanical properties 1,2 .