Roller Quenched Glasses of Bi and Tl High T sub c Compositions

Roller quenching with a cooling rate of about 10 sup 7 K sec sup -1 was used to prepare pure glasses from melts of the high temperature superconductor compositions Bi sub 2 Sr sub 2 CaCu sub 2 O sub (x), Bi sub 2 Sr sub (1.5) Ca sub (1.5) Cu sub 2 O sub (x), Bi sub 2 Sr sub 2 Ca sub 2 Cu sub 3 O sub (x), and Tl sub 2 Ba sub 2 CaCu sub 2 O sub (x).