Microstructure Characterisation and Mechanical Properties of Al-13.5Mg-7Si-2Cu Alloy Produced by Rapid Solidification and Hot Extrusion

J. DURODOLA; F. AUDEBERT; H. ADIL; S. GERGURI; F. SAPORITI; F. BONATESTA

Rome

Congreso; XXV International Symposium on Metastable, Amorphous and Nanostructured Material; 2018

ISMANAM

The alloy Al-13.5Mg-7Si-2Cu (wt.%) was provided by RSP Bv. It was produced by rapid solidification by melt spinning followed by hot extrusion. Characterisation of the microstructure was carried out by means of optical and scanning electron microscopy with an energy dispersed of X-ray analysis. A microstructure formed by a fine dispersion of Si particles and intermetallics in an Al solid solution matrix has been observed. The aging heat treatment conditions were investigated to determine the maximum hardness/strength (T6 condition). The hardness of the alloy increased from 97 HV in as-received state to 165 HV in T6. The hardness of the new alloy is 22% higher than the corresponding to the Al4032 (135 HV in T6). Isothermal treatments at different temperatures were carried out to investigate the thermal stability of the alloy. High temperature tensile tests results showed 2 ? 4.7 times higher strength in piston operation temperature for the new alloy when is compared to the Al4032.