Slurry feedstock for extrusion-based 3d printing of functionally graded articles and casting metal/ceramic article under low pressure at room temperature, methods, and system therefor

A method of preparing a slurry feedstock for extrusion-based three-dimensional, 3D, printing a functionally graded article, characterised in that, the method comprising the steps:

• preparing a build material comprising a metal, a ceramic or any combinations thereof, including:
• providing the build material that is porous, non-porous or any combinations thereof;
• and
• providing the build material in an amount from 10 vol. % to 90 vol. %;
• preparing an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof, including:
• providing the organic polymer binder in a concentration from 150 g/L to 550 g/L;
• preparing an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• preparing a volatile organic solvent;
• and
• forming a first pre-mix by mixing the build material with the additive;
• forming a second pre-mix by mixing the organic polymer binder with the volatile organic solvent;
• mixing the first pre-mix and the second pre-mix to form a substantially homogeneous and flowable slurry mixture that is printed as a preliminary part of the said functionally graded article,
• wherein the organic polymer binder is debound from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment followed by sintering to thereby produce a final part of the functionally graded article containing the build material having selectively varied in composition, structure including infill pattern or any combinations thereof gradually over volume of the final part thereof in one or more directions.

A method of extrusion-based three-dimensional, 3D, printing a functionally graded article, characterised in that, the method comprising the steps:

• providing a slurry feedstock, including:
• preparing a build material comprising a metal, a ceramic or any combinations thereof, including:
• providing the build material that is porous, non-porous or any combinations thereof;
• and
• providing the build material in an amount from 10 vol. % to 90 vol. %;
• preparing an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof, including:
• providing the organic polymer binder in a concentration from 150 g/L to 550 g/L;
• preparing an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• and
• preparing a volatile organic solvent;
• forming a first pre-mix by mixing the build material mixed with the additive;
• forming a second pre-mix by mixing the organic polymer binder dissolved with the volatile organic solvent;
• mixing the first pre-mix and the second pre-mix to form a substantially homogeneous and flowable slurry mixture that is printed as a preliminary part of the said functionally graded article;
• debinding the organic polymer binder from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment;
• and
• subjecting the preliminary part having the organic polymer binder debound therefrom to sintering for producing a final part of the functionally graded article containing the build material having selectively varied in composition, structure including infill pattern or any combinations thereof gradually over volume of the final part thereof in one or more directions.

A system for extrusion-based three-dimensional, 3D, printing a functionally graded article, characterised in that, the system comprising:

• one or more receptacles configured for receiving a slurry feedstock comprising:
• a build material comprising a metal, a ceramic or any combinations thereof,
• wherein the build material is porous, non-porous or any combinations thereof,
• wherein the build material is in an amount from 10 vol. % to 90 vol. %;
• an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof,
• wherein the organic polymer binder is in a concentration from 150 g/L to 550 g/L;
• an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• and
• a volatile organic solvent,
• wherein the build material mixed with the additive and the organic polymer binder dissolved with the volatile organic solvent form a first pre-mix and a second pre-mix, respectively, that are mixed to form a substantially homogeneous and flowable slurry mixture;
• a means for regulating injection of the slurry feedstock contained in the one or more receptacles thereof,
• wherein the means for regulating injection is selected from a group comprising a solenoid valve, a mechanical pump and a combination thereof;
• a computing unit comprising a control unit configured for generating a control signal to the said means for regulating injection,
• wherein the control unit is connected to a database comprising a predefined set of material and rheology profiles employed to operatively effect the control signal in respect of a final part of the said functionally graded article;
• a fluid drive device configured for providing a fluidic pressure to the slurry feedstock contained in the one or more receptacles thereof or to the means for regulating injection, which, in turn, actuates the slurry feedstock in the one or more receptacles connected thereof to provide a pressurized slurry feedstock,
• wherein the fluid drive device is selected from a group comprising a pneumatic drive device, a hydraulic drive device, a mechanical displacement device and any combinations thereof;
• and
• a print head operatively driven by the computing unit thereof configured for jetting the said substantially homogeneous and flowable slurry mixture to produce a preliminary part of the said functionally graded article,
• wherein the organic polymer binder is debound from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment followed by sintering to thereby produce the final part of the functionally graded article containing the build material having selectively varied in composition, structure including infill pattern or any combinations thereof gradually over volume of the final part thereof in one or more directions.

A slurry feedstock for casting an article under a low pressure at a room temperature, characterised in that, the slurry feedstock comprising:

• a build material comprising a metal, a ceramic or any combinations thereof,
• wherein the build material is porous, non-porous or any combinations thereof,
• wherein the build material is in an amount from 10 vol. % to 90 vol. %;
• an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof,
• wherein the organic polymer binder is in a concentration from 50 g/L to 550 g/L;
• an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• and
• a volatile organic solvent,
• wherein the build material mixed with the additive and the organic polymer binder dissolved with the volatile organic solvent form a first pre-mix and a second pre-mix, respectively, that are mixed to form a substantially homogeneous and flowable slurry mixture that is subjected to moulding in a cavity of a mould substantially immersed in a coagulation bath for producing a preliminary part of the said article by way of phase inversion,
• wherein the organic polymer binder is debound from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment followed by sintering to thereby produce a final part of the article.

A method of preparing a slurry feedstock for casting an article under a low pressure at a room temperature, characterised in that, the method comprising the steps:

• preparing a build material comprising a metal, a ceramic or any combinations thereof, including:
• providing the build material that is porous, non-porous or any combinations thereof;
• and
• providing the build material in an amount from 10 vol. % to 90 vol. %;
• preparing an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof, including:
• providing the organic polymer binder in a concentration from 50 g/L to 550 g/L;
• preparing an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• preparing a volatile organic solvent;
• and
• forming a first pre-mix by mixing the build material with the additive;
• forming a second pre-mix by mixing the organic polymer binder with the volatile organic solvent;
• mixing the first pre-mix and the second pre-mix to form a substantially homogeneous and flowable slurry mixture that is subjected to moulding in a cavity of a mould substantially immersed in a coagulation bath for producing a preliminary part of the said article by way of phase inversion;
• wherein the organic polymer binder is debound from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment followed by sintering to thereby produce a final part of the article.

A method of casting an article under a low pressure at a room temperature, characterised in that, the method comprising the steps:

• providing a slurry feedstock, including:
• preparing a build material comprising a metal, a ceramic or any combinations thereof, including:
• providing the build material that is porous, non-porous or any combinations thereof;
• and
• providing the build material in an amount from 10 vol. % to 90 vol. %;
• preparing an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof, including:
• providing the organic polymer binder in a concentration from 50 g/L to 550 g/L;
• preparing an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• and
• preparing a volatile organic solvent;
• forming a first pre-mix by mixing the build material mixed with the additive;
• forming a second pre-mix by mixing the organic polymer binder dissolved with the volatile organic solvent;
• mixing the first pre-mix and the second pre-mix to form a substantially homogeneous and flowable slurry mixture;
• subjecting the said substantially homogeneous and flowable slurry mixture to moulding in a mould;
• substantially immersing the mould having a cavity filled with the substantially homogeneous and flowable slurry mixture thereof in a coagulation bath to produce a preliminary part of the said article by way of phase inversion;
• debinding the organic polymer binder from the preliminary part in either or both a thermal decomposition treatment and a solvent debinding treatment;
• and
• subjecting the preliminary part having the organic polymer binder debound therefrom to sintering for producing a final part of the article.

A system for casting an article under a low pressure at a room temperature, characterised in that, the system comprising:

• one or more receptacles configured for receiving a slurry feedstock comprising:
• a build material comprising a metal, a ceramic or any combinations thereof,
• wherein the build material is porous, non-porous or any combinations thereof,
• wherein the build material is in an amount from 10 vol. % to 90 vol. %;
• an organic polymer binder selected from a group comprising a cellulose ester, a cellulose ether, and derivatives thereof,
• wherein the organic polymer binder is in a concentration from 50 g/L to 550 g/L;
• an additive selected from a group comprising a plasticizer, a defoaming agent, a dispersing agent, a sacrificial material, a fugitive material, a scaffolding material, a water-soluble inorganic salt, a foaming agent, a graphene, a graphene oxide, a flame retardant, a toner, a release additive, a stabilizer, an anti-static agent, an impact modifier, a colourant, an antioxidant and any combinations thereof;
• and
• a volatile organic solvent,
• wherein the build material mixed with the additive and the organic polymer binder dissolved with the volatile organic solvent form a first pre-mix and a second pre-mix, respectively, that are mixed to form a substantially homogeneous and flowable slurry mixture;
• a mould configured for moulding the said substantially homogeneous and flowable slurry mixture received from the one or more receptacles thereof;
• and
• a coagulation bath configured for substantially immersing the mould having a cavity filled with the substantially homogeneous and flowable slurry mixture therein to produce a preliminary part of the said article by way of phase inversion;
• and
• a means for debinding the organic polymer binder from the preliminary part, wherein the means for debinding comprises either or both a thermal decomposition treatment and a solvent debinding treatment followed by sintering to thereby produce a final part of the article.

A feedstock composition for three-dimensional, 3D, printing, characterised in that, the feedstock comprising:

• a build material;
• and
• a binder solution,
• wherein the binder solution is selected from the group consisting of cellulose ester, cellulose ether, and its derivatives,
• wherein the composition is adapted into a slurry mixture form.

A three-dimensional, 3D, printed article, characterised in that, the 3D printed article comprising:

• a build material;
• and
• a binder solution,
• wherein the binder solution is selected from the group consisting of cellulose ester, cellulose ether, and its derivatives,
• wherein the composition is adapted into a slurry mixture form.

A method of preparing feedstock material for three-dimensional, 3D, printing, characterised in that, the method comprises steps:

• preparing a binder solution selected from the group consisting of cellulose ester, cellulose ether, and its derivatives;
• and
• mixing a build material and the binder to form a slurry mixture,
• wherein the feedstock material can be directly pumped to a nozzle for printing.