Synthesis of a La-based bulk metallic glass matrix composite

Abstract

A bulk metallic glass matrix composite, that is a crystalline phase in an amorphous matrix, has been successfully synthesized by chill casting a La-based quaternary La₆₆Al₁₄Cu₁₀Ni₁₀ alloy. A composite rod as large as 12 mm in diameter was obtained. The reinforcing crystalline phase was identified as α-La, which was uniformly distributed and well developed throughout the sample. The critical cooling rate for the formation of the composite was determined by the Bridgman solidification process to be below 15 K s⁻¹. Increased thermal stability was observed for the composite compared with the fully glassy rods, the reason for which remains unclear.