COMPARATIVE STUDY OF THE METALLURGICAL PROPERTIES AND CORROSION RESISTANCE OF THE EN AC-46500 ALUMINUM ALLOY OBTAINED BY HIGH PRESSURE DIE CASTING AND BY MOLDING IN SEMI SOLID STATE

Abstract

This article explores the new possibilities that injection moulding process known as Semi Solid Rheocasting (SSR) could offer, whose main innovation lies in the fact that the material is injected in semisolid state, whereas in the traditional method of casting (HPDC) the material is in liquid state. Although the process SSR is already stablished in some enterprises at the state level, the improvements that could have the components obtained by this process could lead to increased interest of new companies. The study is focused on the same alloy, the EN AC-46500, which is submitted to the processes mentioned above. A comparison between components obtained through both processes, have been done by means of the analysis of microstructural characteristics, mechanical properties and resistance to corrosion. The microstructure has been analysed by optical microscopy, using different solutions where have been submerged the samples to observe with greater clarity the grains and the components of the alloy. The samples have also been studied using scanning electron microscopy, with the purpose of establishing the type of breakage which have suffered after having been tested mechanically. The mechanical properties of the material, have been measured through mechanical tensile tests and by Charpys pendulum impact tests. Finally, accelerate corrosion tests have been done in a salt spray chamber and in a Kesternich or SO2 chamber to determine the resistance of the material against corrosion. At the same time, to confirm what has been observed in the corrosion tests mentioned, corrosion testing has been carried out with electrochemical tests to measure the rate of corrosion in the components object of this study. Key Words: EN AC-46500 alloy, Aluminium, Characterization, HPDC, injection moulding, SSR.