Slurry processing of nanoscale materials into nanotechnology products
Methods for slurry processing of nanomaterials into products. These methods are useful for organic, inorganic, metallic, alloy, ceramic, conducting polymer, non-conducting polymer, ion conducting, non-metallic, ceramic-ceramic composite, ceramic-polymer composite, ceramic-metal composite, metal-polymer composite, polymer-polymer composite, metal-metal composite, processed materials including paper and fibers, and natural materials such as mica, dielectrics, ferrites, stoichiometric, non-stoichiometric, or a combination of one or more of these. These methods also allow the fabrication of a functionally graded products.
1 . A method for transforming nanoscale powders into a product comprising:
providing nanoscale powders;
preparing a dispersion comprising the nanoscale powders and a liquid medium;
tape casting the dispersion into layers with a thickness between 0.1 to 1000 microns;
producing a laminated structure comprising two or more tape casted layers wherein the laminated structure is formed by stacking the layers; sectioning the laminated structure to produce a product with desired geometry; and
sintering the product with desired geometry thereby producing a densified product.
2 . The method of claim 1 further comprising a step wherein the densified product undergoes one or more finishing operations selected from the group consisting of polishing, terminating, electroding, passivating and packaging,.
3 . The method of claim 1 wherein the dispersion comprises a slurry, slip or ink.
4 . The method of claim 1 wherein the liquid medium comprises an aqueous or non-aqueous solvent.
5 . The method of claim 1 wherein the liquid medium comprises one or more substance selected from the group consisting of dispersants, alcohols, ketones, and hydrocarbons.
6 . The method of claim 1 wherein the formulated dispersion comprises a mixture of nanoscale powders and micron sized powders.
7 . The method of claim 1 wherein the formulated dispersion comprises a mixture of nanoscale powders, submicron powders and micron sized powders.
8 . The method of claim 1 wherein the thickness is between 0.1 to 1 micron.
9 . The method of claim 1 wherein the laminated structure comprises one or more active layers and one or more non-active layers.
10 . The method of claim 1 wherein the nanoscale powders comprise a composition selected from the group consisting of: silicon carbide, titanium oxide, barium titanate, strontium titanate, zinc oxide, zinc sulfide, indium oxide, zirconium oxide, tin oxide, antimony oxide, tungsten oxide, molybdenum oxide, tantalum oxide, cerium oxide, rare earth oxides, silicon carbide, hafnium carbide, bismuth telluride, gallium nitride, silicon, germanium, iron oxide, titanium boride, zirconium boride, zirconates, aluminates, tungstates, carbides, manganates, ruthenates, borates, hydrides, oxides, oxynitrides, oxycarbides, halides, silicates, phosphides, nitrides, chalcogenides, dielectrics and ferrites.
11 . The method of claim 1 wherein the nanoscale powders comprise a purity greater than 99.9% by metal basis.
12 . The method of claim 1 wherein the nanomaterials comprise an aspect ratio greater than 1.
13 . The method of claim 1 wherein the stacking is manual, automatic, computer aided, optically aligned or robotically aligned.
14 . The method of claim 1 wherein at least one layer in the laminated structure is an electrode.
15 . The method of claim 1 wherein at least one layer in the laminated structure provides an electrical, thermal, magnetic, electromagnetic, optical, or structural function.
16 . The method of claim 1 wherein the laminated structure creates a functionally graded material.
17 . The method of claim 1 wherein the dispersion is prepared by ball milling, ultrasonic agitation or shear homogenization.
18 . The method of claim 1 further comprising a step prior to the sintering step wherein the product with desired geometry is pressed and cured.
19 . The method of claim 1 wherein the sintering step produces a fully densified product.
20 . The method of claim 1 wherein the product is selected from the group consisting of: surgical blades, cryogenic slicing tools, blades for cutting polymers and fabrics, blades for scissors, knives, seal, filter, implants, sensors, drug delivery devices, varistors, inductors, capacitors, batteries, EMI filters, interconnects, resistors, thermistors, device arrays, magnetic components, thermoelectric devices, gradient index optics, optoelectronic components, biomedical products, electronic, telecom, optics, electrical, photonic, thermal, piezo, catalytic, fuel cell and electrochemical components.