High Specific Strength and Improved Ductility of Bulk (Mg_0.65Cu_0.25Gd_0.1)_100−xTi_x Metallic Glass Composites

Abstract

The monolithic Mg₆₅Cu₂₅Gd₁₀ bulk metallic glass always shows brittle fracture with a plastic strain of near zero even under a compressive load. Improved ductility and enhanced compressive strength were simultaneously achieved at room temperature in (Mg_0.65Cu_0.25Gd_0.1)_100−xTi_x (x=0, 2.5, 5 and 7.5 at%) metallic glass composites. The compressive strength (σ_f) reached 940 MPa, and a plastic strain (ε_p) of about 0.8% was undergone for the bulk metallic glass composite at x=5. The glass composites were formed by doping Mg₆₅Cu₂₅Gd₁₀ bulk metallic glass with adequate lightweight titanium with a density near that of Mg₆₅Cu₂₅Gd₁₀ bulk metallic glass. The composite sustains the features of lightweight and very high specific strength which are the same as those of the Mg-based bulk metallic glass. Thus, the addition of Ti does not cause distinctly harmful influence on the glass-formation ability of the matrix glass.