Hybrid slip casting-electrophoretic deposition (EPD) process
AssigneeSan Diego State University (SDSU) Foundation
InventorsEugene Olevsky, Xuan Wang, Margaret Stern
Life of this patent
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Abstract
The invention provides novel a hybrid slip casting-Electrophoretic Deposition (EPD) process which can be used to produce arbitrary shape geometries with controlled materials properties. The invention provides processes for the fabrication of Functionally Graded Materials (FGM) by a controlled Electrophoretic Deposition (EPD).
Claims20
A hybrid slip casting—Electrophoretic Deposition (EPD) process comprising a process as set forth in FIG. 2,
- wherein the process is practiced in a product of manufacture for hybrid slip casting—Electrophoretic Deposition (EPD) comprising a system as set forth in FIG. 1,
- wherein the system comprises a deposition cell comprising a deposition electrode and a counter electrode, and a deposition bath in the deposition cell, and a porous mold introduced into the deposition bath between the deposition and the counter electrodes,
- and optionally the a porous mold is a porous plaster mold.
A product of manufacture for hybrid slip casting—Electrophoretic Deposition (EPD) comprising a system as set forth in FIG. 1,
- wherein the system comprises a deposition cell comprising a deposition electrode and a counter electrode, and a deposition bath well in the deposition cell, and a porous mold introduced into the deposition bath well between the deposition and the counter electrodes to produce two wells,
- and optionally the a porous mold is a porous plaster or a porous gypsum mold.
An Electrophoretic Deposition-Slip casting method for near net shaping of articles comprising the following steps:
- (a) preparing a porous mold conforming to the shape of a desired casting geometry, wherein optionally the mold comprises a gypsum mold;
- (b) preparing at least one suspension (slurry) to be used to deposit the articles desired,
- wherein optionally the at least one suspension (slurry) comprises a powder comprising a metal, ceramic, polymer or an equivalent compound or any combination thereof,
- and also optionally comprises a particle-charging additive,
- and optionally the at least one suspension (slurry) comprises a surfactant, which optionally comprises at least one, several or all of a dispersant, an electrosteric stabilizer, an electrostatic dispersant, a binders, wherein optionally the binder comprises phosphate ester;
- (c) assembling the mold of step (a) in a silicone mold, or equivalent mold, wherein the mold of step (a) separates the said silicone or equivalent mold into two impermeable chambers;
- (d) placing two electrodes at two ends of the said silicone or equivalent mold;
- (e) pouring the at least one suspension (slurry) into a chamber A in the said silicone or equivalent mold,
- wherein optionally at least two suspensions (slurries) are added sequentially, or together (simultaneously);
- (f) pouring an ionic solution into a chamber B of the said silicone or equivalent mold;
- (g) applying an electric field to the said electrodes,
- wherein optionally the electric field comprises an external electric field;
- (h) adding the said suspension (slurry) to the said chamber A of the said silicone mold or equivalent,
- wherein optionally the addition is by a circulation pump;
- (i) drying the deposited suspension (slurry) (article) in the said mold of step (a) (optionally a gypsum mold) after deposition is complete;
- and
- (j) removing the casting from the said mold of step (a) and sintering or firing the article,
- wherein optionally the sintering or firing comprises a microwave sintering, pressureless sintering, hot isostatic pressing and/or by hot pressing in a rigid die.
Dependencies are inferred from the claim text.