Abstracts Book - IMRC 2018

• SD6-O016
HOMOGENEITY OF CO-MILLED POWDERS OF A356 ALUMINUM
ALLOY AND Si3N4.
Heydi Milagros Fernández Echevarría 1,2 , Matteo Leoni 2 , Stella Ordoñez 1
1 Universidad de Santiago de Chile, Department of Metallurgical Engineering, Chile. 2 Università
degli Studi di Trento, DICAM, Italy.
The ball milling of aluminium alloy A356 with different mass fractions (10, 20 and
30%) of Si 3 N 4 powders was carried out in a planetary mill in order to obtain a
composite A356-Si 3 N 4 alloy. The structural modifications at different stages of
the mechanical milling were investigated with X-ray powder diffraction (XRPD)
using Scherrer formula and Whole Powder Pattern Modeling (WPPM). Due to the
inhomogeneity of the microstructure of the starting powder and of the milling
process, the WPPM of XRPD data required the hypothesis of a multimodal
distribution and the coexistence of two Al phases with different Si content. By
increasing the milling time and the amount of reinforcing particle, the silicon
and microstructure inhomogeneity decrease and a monomodal lognormal
distribution is enough to data modelling.
Acknowledgment:
The authors would like to thank Project 1150268 FONDECYT for financial
support and the support of CONICYT, Doctorado Nacional 2015 Ph.D. Grant.
Keywords: mechanical milling, microstructure inhomogeneity, WPPM
Presenting authors email: heydi.fernandez@usach.cl