Thixocasting semi-molten casting material and its mfr. - the material comprising composite solid phases each having liq. and solid phases, and single solid phases

摘要

Thixocasting semi-molten casting material having solid and liquid phases coexisting in it comprises a number of composite solid phases each having a liquid phase region and a solid phase region enclosing the liquid phase region, and a number of single-solid phases having no liquid phase region. The composite solid phases and the single solid phases are mixed as the solid phases in an outer layer portion of the semi-molten casting material. If a liq. enclosure rate P of one of the composite solid phases is defined as: P = (B/(A+B)) x 100 (%) (where A = sectional area of the solid phase region; and B = sectional area of the liquid phase region), and the liq. enclosure rate P of the single solid phase is defined as: P = O (%), and if N number of groups are selected from a class of the solid phases in the outer layer portion so as to include a no. of the solid phases, the average values Ml to Mn of liq. enclosure rates P1, P2....Pn-1 and Pn of an n no. of solid phases in first to N-th gps. are represented by M1=(P1+P2....+Pn-1+Pn)/n to Mn=(P1+P2....+Pn-1+Pn)/n and an average value Mm=(M1+M2....+Mn-1+Mn)/N of the average values M1 to Mn is in a range of Mm = at least 20%. Prodn. of the material is also claimed.