Abstract: The new technique improving segregations in non-ferrous cast metals is called Thermal-Rate Treatment. By the technique, the microsegregation and microsegregation in Pb-Sb and Al-Cu alloys are greatly improved. The micresogregation coefficient K, of hypoeutectic Pb-8%Sb alloy changed from 0.056 into 0.635 after treatment by the technique. The mechanism of the new technique to improve the segregations has been studied according to the theory that the structures of liquid metals are related to the segregation.

Key words: Metal liquid, Pb-Sb alloy, Repid solidification alloy, Segregation