Metal founding – Process – Shaping a forming surface
Patent
1993-09-09
1994-10-18
Bradley, P. Austin
Metal founding
Process
Shaping a forming surface
164529, B22C 702
Patent
active
053559312
ABSTRACT:
A method of producing dimensionally predictable metal castings utilizing an expendable polymeric foam pattern along with unbonded sand having specific thermal properties. The pattern, formed of a material such as polystyrene, has a configuration corresponding to that of the article to be cast. The pattern is placed with an outer flask and unbonded sand surrounds the pattern as well as filling the cavities in the pattern. The sand has a linear expansion of less than 1% from 0.degree. C. to 1600.degree. C., a heat diffusivity greater than 1500 J/m.sup.2 /.degree.K/S1/2, an AFS grain fineness number of 25 to 33, and an AFS base permeability number of 450 to 500. A molten metal, such as an aluminum alloy or a ferrous alloy, is fed into the mold in contact with the pattern causing the pattern to vaporize with the vapor being entrapped within the interstices of the sand while the molten metal fills the space initially occupied by the foam pattern to produce a cast article. The physical properties of the sand enable articles to be cast having more precise and predictable tolerances.
REFERENCES:
patent: 3333579 (1967-08-01), Shockley
patent: 3536123 (1970-10-01), Izumi
patent: 4113473 (1978-09-01), Gauvry
patent: 4139045 (1979-02-01), Vitt
patent: 4603665 (1986-08-01), Hesterberg et al.
patent: 4693292 (1987-09-01), Campbell
patent: 4711287 (1987-12-01), Kuwabara et al.
patent: 4804032 (1989-02-01), Wilkins
patent: 4821694 (1989-04-01), Hesterberg et al.
patent: 4875517 (1989-10-01), Donahue et al.
patent: 4902475 (1990-02-01), Apelain et al.
patent: 4966220 (1990-10-01), Hesterberg et al.
patent: 4969428 (1990-11-01), Donahue et al.
patent: 5129378 (1992-07-01), Donahue et al.
Metals Handbook, 9th Ed., vol. 15, p. 233, Sep. 1988.
Cleary Terrance M.
Donahue Raymond J.
Hesterberg William G.
Holmgren Terry C.
Bradley P. Austin
Brunswick Corporation
Puknys Erik R.
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