Castable zinc-aluminum alloys
AssigneeQueen's University at Kingston
InventorsReginald W. Smith, Mansor Ghoreshy
Life of this patent
Estimating the term…
Abstract
An improved castable hypereutectic zinc-aluminum alloy which is free from underside shrinkage is described. Small additions, from about 0.25% and up to about 2 wt% of rare earth metal, preferably in the form of misch metal, to known zinc-aluminum alloys containing from about 20% and up to about 40 wt% aluminum have been found to prevent underside shrinkage in castings with a cross section up to about six inches.
Claims8
A method for controlling underside shrinkage in a cast hypereutectic zinc-aluminum alloy containing at least about 20 wt% aluminum comprising melting said alloy and adding thereto at least one rare earth metal in an amount between 0.25 wt% and 2.0 wt% and sufficient to substantially eliminate underside shrinkage when said alloy is cast into a sand mould having a cross section of at least one inch, and subsequently casting said rare earth metal containing alloy into a mould.
A castable, hypereutectic zinc-aluminum alloy consisting essentially of:
- at least 20 wt% to about 40 wt% aluminum
- from 0.25 wt% to 2 wt% of at least one rare earth metal
- up to 5.0 wt% Cu
- up to 1.0 wt% Si
- up to 0.1 wt% Mg
- balance zinc and incidental impurities.
Dependencies are inferred from the claim text.