Effects of extrusion conditions on mechanical properties in Zr-Al-Ni-Cu glassy powder compacts

We report on extrusion conditions such as the powder handling processing and extrusion ratio and temperature in the production of glassy alloy compacts by means of the warm extrusion of powders at a supercooled liquid state. The alloy used was a Zr₆₅Al₁₀Ni₁₀Cu₁₅ (at.%) glassy alloy which has a significant supercooled liquid region of 105 K. The glassy powder compacts with almost the same tensile strength as the melt-spun glassy ribbons or the as-cast glassy bulks were produced by an extrusion in the supercooled liquid state at extrusion ratios above 4 by means of ordinary powder metallurgy processing. Closed processing, in which the powder was handled in a well-controlled atmosphere without being exposed to air, moreover, led to a higher level of strength as compared with ordinary processing, and full strength at extrusion ratios above 3, due to improvement in the powder particle bonding state. This seems to greatly affect the future development of bulk amorphous alloys that have complex shapes and novel properties.