The application of a high-pressure die casting technique to La-Al-TM (TM = Co, Ni, Cu) alloys was found to produce bulk amorphous alloys in cylinder and sheet forms. The maximum sample diameter (dc) for formation of an amorphous phase is 3 mm for La55Al25(Ni or Cu)20, 7 mm for La55Al25Ni10Cu10 and above 9 mm for La55Al25Cu10Ni5Co5. There is a clear tendency for dc to increase with an increase in the temperature interval of a supercooled liquid region. The glass transition temperature (Tg), the crystallization temperature (Tx) and the heat of crystallization (ΔHx) remain unchanged in the thickness range of 1 to 7 mm for the La55Al25Cu10Ni10 alloy. Tg and ΔHx are nearly the same as those for the melt-spun ribbon. The tensile fracture strength (σf) and elongation (εf) for the La65Al20Cu7.5Ni3.75Co3.75 cylinder with a diameter of 3 mm are 700 MPa and 1.5%. Although the εf value is nearly the same as that for the melt-spun ribbon, the σf value is about 80% as high as that for the ribbon. The decrease in σf by 20% is presumably due to the existence of pores based on the result that the porosity of the cast samples is about 20%. The achievement of the σf for the cast alloys with 20% in porosity indicates that the bulk amorphous alloys also have a ductile nature which is comparable to that for the melt-spun ribbon.
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