AbstractTwo types of Co base amorphous alloy powders produced by a cavitation method were warm pressed below crystallisation temperatures. Compacts with>99% relative density were produced in an amorphous state. Compacts formed from fine powders were superior in mechanical properties, but inferior in magnetic properties to those formed from coarse powders. It was indicated by the geometry of fracture surfaces in compression tests that for amorphous compacts yield was in accordance with the von Mises criterion.MST/944