High temperature mechanical properties of Mg-Y2O3 composite:: Competition between texture and reinforcement contributions

The effect of the addition of hard ceramic particles on the mechanical properties at high temperature of pure magnesium has been investigated. The composite and the unreinforced magnesium presents higher stress exponent values (n = 11-16). This fact has been explained by means of the strong fiber of the {10 (1) over bar0} planes perpendicular to the extrusion direction, the presence of the yttria particle in the composite and the presence of oxide particle due to the use of a powder metallurgy route. The reinforcement effect due to the texture is effective up to 300 degrees C. The activation of non-basal slip system results in the disappearance of this effect and the composite present higher flow stress compared with the unreinforced magnesium. (c) 2006 Elsevier Ltd. All rights reserved.