Extremely wide supercooled liquid region and large glass-forming ability in Zr₆₅ - xAl_7.5Cu_17.5Ni₁₀Be_x amorphous alloys

The temperature interval of the supercooled liquid region before crystallization in Zr_{65 - x}Al_7.5Ni₁₀Cu_17.5Be_x alloys is the largest for the x = 0 alloy. It is therefore said that the addition of Be with an extremely small atomic size as compared with those of the other constituent elements is not effective for further extension of the wide supercooled liquid region. The quenching of the melt in a quartz tube into water was found to enable the production of bulk amorphous alloy in cylindrical form with a diameter of 16 mm and a length of 150 mm for the Zr₆₅Al_7.5Ni₁₀Cu_17.5 alloys with the largest ΔT_x of 127 K. The finding of the extremely large glass-forming ability of the ZrAlNiCu alloy is very important for subsequent development of metallic amorphous alloys.