ENCYCLOPÉDIE DE LA RECHERCHE SUR L’ALUMINIUM AU QUÉBEC 2013 | Page 51

NOUVEAUX PRODUITS ET MATÉRIAUX À BASE D'ALUMINIUM
NEW ALUMINIUM BASED PRODUCTS AND MATERIALS

Mechanical Properties and Fracture
Mechanisms of Al-B4C Based Metal Matrix MÉCANISMES DE RUPTURE
PROPRIÉTÉS MÉCANIQUES ET
Composites
DES COMPOSITES À MATRICE MÉTALLIQUE DE TYPE Al-B4C

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Propriétés mécaniques et mécanismes de rupture FRACTURE MECHANISMS OF
PROPERTIES AND
Al-B4C Al-B4 METAL MATRIX COMPOSITES
des composites à matrice métallique de type BASEDC
M.F. Ibrahim,a H.R. Ammar,b A.M. Samuel,a M.S. Solimanc and F.H. Samuela,b
King Saud University

a Université

du Québec à Chicoutimi, Québec, Canada, G7H 2B1
Manufacturing Institute , King Saud University, Riyadh, Saudi Arabia
C Mechanical Engineering Department, College of Engineering, King Saud University, Riyadh, Saudi Arabia
bAdvanced

1. Introduction

King Saud University

4. Results

In this study, Al-15vol% B4C MMCs were homogenized at elevated temperatures for 48 hrs
and aged in the range of 25-400°C for 10 hrs. Hardness and tensile tests performed on the
aged MMCs show that the presence of Zr (with/without Ti) resulted in a noticeable hardening
due to the precipitation of a Zr-rich phase. Maximum strengthening was obtained from the
6063-based MMC due to the precipitation of Mg2Si phase particles. The present technique
used to produce the MMCs examined proved capable of manufacturing composites with a
uniform distribution of B4C in the matrix with a strong degree of matrix/particle bonding. It
was found that when the MMC samples were deformed to failure, the B4C fractured
transgranularly, without debonding from the matrix. The addition of Zr and Ti resulted in
the formation of protective layers around the B4C particles which persisted after fracture;
and were not affected by the B4C particle size (0.15-20μm). Stacking faults were commonly
observed on the fracture surface of Al 6063/B4C/15p. The precipitation of zirconium-titanium
compounds during aging contributed to the composite strength.

Fe-based intermetallic
Alloy B
)