A NEW APPROACH TO SYNTHESIS OF BULK AMORPHOUS ALLOYS BY USING HIGH-PRESSURE COMPACTION OF THE MELT-SPUN AMORPHOUS RIBBONS
非晶态合金条带高压复合法制备大块非晶态合金

A hot high-pressure compaction of melt--spun amorphous metallic ribbons which produces fully-densed bulk amorphous samples, was developed by using an amorphous Ni69Cr7Fe2.5Si8B13.5 alloy ribbons as a model material. Under a pressure of 1.5GPa, the crystallization onset temperature was found to be increased by about 40K, resulting in a widened supercooled liquid temperature region of about 60K beneath the onset of crystallization. Consolidation of the amorphous ribbons in temperatures of 733~ 773 K with a pressure higher than 1.5GPa yielded bulk amorphous compacts with full density (>99% of the theoretical value). This achievement was attributed to the significant homogenous viscous flow of materials in the supercooled liquid state.