Cu-based bulk amorphous alloy with larger glass-forming ability and supercooled liquid region

摘要

The glassy rod with a maximum sample thickness of 11 mm and larger supercooled liquid region of 108 K was successfully fabricated when substituting Cu with minor amount of Ag in the Cu-Zr-Al-Gd alloy system. The value of gamma reaches a maximum of 0.418 for the Cu_(45.5)Zr_(45)Al_7Gd_2Ag_(0.5) bulk metallic glass (BMG) alloy. The high glass-forming ability (GFA) and larger supercooled liquid region are discussed from atomic size, negative mixing heat among constituent elements and thermodynamics.