Synthesizing of Novel Bulk (Zr67Cu33)100−xWx(x; 5–30 at) Glassy Alloys by Spark Plasma Sintering of Mechanically Alloyed Powders

摘要

Metallic glassy alloys with their short-range order have received considerable attention since their discovery in 1960’s. The worldwide interest in metallic glassy alloys is attributed to their unique mechanical, physical, and chemical properties, which cannot be found together in long-range order alloys of the same compositions. Traditional preparation methods of metallic glasses, such as rapid solidification of melts, always restrict the formation of glassy alloys with large atomic fraction (above 3–5 at%) of high melting point metals (Ta, Mo, W). In this study, (Zr Cu ) W ( ; 5–30 at%) metallic glassy alloys were fabricated through a mechanical alloying approach, which starts from the elemental powders. This system shows excellent glass forming ability in a wide range of W (0 ≤ ≥ 30 at%). We have proposed a spark plasma sintering technique to prepare nearly full-dense large sized (20 × 20 mm) bulk metallic glassy alloys. The as-consolidated bulk metallic glassy alloys were seen to possess high thermal stability when compared with the other metallic glassy systems. This is implied by their high glass transition temperature (722–735 K), wide range of supercooled liquid region (39 K to over 100 K), and high values of crystallization temperature (761 K to 823 K). In addition, the fabricated ternary systems have revealed high microhardness values.