High strength and fracture toughness balance on the extruded Mg-Ca-Zn alloy

The mechanical properties were investigated by Mg-0.3 at.% Ca-1.8 at.% Zn alloy, which was produced by hot extrusion, having an average grain size of about 1 mu m and spherical precipitates in the matrix. The extruded alloy showed a good balance of the yield strength (sigma(ys) = 291 MPa) and plane-strain fracture toughness (K-IC = 28.3 MPa m(1/2)), obtained by the stretched zone analysis, which were higher than those of conventional wrought magnesium alloys. The microstructure control of both the grain refinement and the dispersion of precipitates in the matrix was a possible method for improvement of the mechanical properties in magnesium alloys. (C) 2007 Elsevier B.V. All rights reserved.