| 摘要 |
PURPOSE:To form composite castings of uniform quality with good productivity by forming molten metal into semimolten composite metal in a crucible having a vertical paddle of specific construction, adding addition agents suitably and dispersing these uniformly then injecting the metal through an injection sleeve. CONSTITUTION:The molten alloy in a tundish 30 is flowed into a crucible 26 by means of a chute 27 for introduction of molten metal, after which a cover 31 is closed. At the same instant of the inflow, a paddle 36 is rotated, thence a heat source 23a is controlled, whereby the molten metal is maintained at solid- liquid coexistence temps. The initial crystal crystallized during this time assumes spherical shapes by receiving the shearing by the paddle 36, and the molten metal turns to a semimolten slurry. Next, if necessary, granular or fibrous addition agents are added from an addition agent storage hopper 33, and these are uniformly dispersed by means of impellers 40, 41, 42. Next, a plunger tip 48 is retreated, and the slurry is discharged through a supply port 47 into an injection sleeve 46, thence the tip 48 is advanced, whereby it is injected in a short time into a mold. |
