METAL COMPOSITION SUITABLE FOR PRODUCING SEMI-SOLID SEMI-LIQUID STATE AND MANUFACTURE

摘要

The invention relates to a process for preparing a fine grained metal composition and to the compositions so produced. …??Said fine grained metal composition is suitable for forming in a partially solid, partially liquid condition. The compostion is prepared by producing a solid metall composition having an essentially directional grain structure and heating the directional grain composition to a temperature above the solidus and below the liquidus to produce a partially solid, partially liquid mixture containing at least 0.05 volume fraction liquid. The composition, prior to heating, has a strain level introduced such that upon heating, the mixture comprises uniform discrete spheroidal particles contained within a lower melting matrix. The heated alloy is then solidified while in a partially solid, partially liquid condition, the solidified composition having a uniform, fine grained microstructure.