3D PRINTING METHOD USING SLIP

20220024068 · 2022-01-27

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention relates to a 3D printing method, a device and molded parts produced with the aid of this method.

    Claims

    1. A method for producing three-dimensional molded parts in a device, comprising the following steps: a. producing a material layer by applying a slurry with an application means onto a contruction plane in a predetermined layer thickness, the slurry comprising a carrier fluid and particulate material, wherein the particulate material is or comprises an at least partially fusible material, wherein the particulate material is a sinterable material and is selected from the group consisting of a thermoplastic, a polyconsensate, preferably a polyamide (PA), metallic and/or ceramic particles or a mixture thereof; b. applying a liquid binder material to selected areas of the material layer; c. inputting energy for sintering or at least partial fusion, wherein the energy takes place in the form of electromagnetic energy, by means of a radiator in the IR-A or/and IR-B range or by means of an IR radiator or by means of a laser, d. lowering the construction plane by a desired layer thickness or raising the application means and, if necessary, other means of the device by a desired layer thickness; e. repeating steps a.) through d); wherein the binder material contains or consists of an energy-absorbing material, said energy-absorbing material containing graphite or carbon black, and absorbs and releases energy and heat to the surrounding material, thereby causing a local temperature increase; f. removing the material surrounding the molded parts to obtain the molded parts.

    2. The method of claim 1, wherein the construction plane is arranged in a construction space.

    3. The method of claim 1, wherein the process conditions are selected such that the molded part is formed by at least partially selectively fusing the fusible material in the slurry in the process.

    4. The method of claim 1, wherein the carrier fluid is selected from the group consisting of water and an organic solvent.

    5. The method of claim 1, wherein the application means is a coating device, optionally wherein the desired layer thickness of the material layer remains constant for each slurry application.

    6. The method of claim 1, wherein a temperature of the construction platform or/and the construction space is adjusted, optionally the temperature adjustment is carried out with means outside or inside the build space, optionally the construction platform being heated or irradiated with IR.

    7. The method of claim 1, wherein the temperature of the construction platform or/and the construction space is adjusted to a temperature of 40° C. to 200° C.

    8. The method of claim 1, wherein the temperature of the construction platform or/and the construction space is adjusted to a temperature of 150° C. to 190° C.

    9. The method of claim 1, wherein the temperature in the last material layer is adjusted to 190° C. to 210° C.

    10. The method of claim 1, wherein the molded part is unpacked in a liquid bath, by adding an aqueous liquid to a material block including the molded part, or by spraying it off with an aqueous liquid.

    11. The method of claim 1, wherein the binder material is applied by a printing device.

    12. The method of claim 1, wherein the slurry is mixed together from the particulate material and the carrier fluid, shortly before application.

    13. The method of claim 1, the material layer results from the removal of the carrier fluid, optionally be evaporation, optionally less than 90 seconds per material layer.

    14. The method of claim 1, wherein the particulate material has an average diameter of 1 to 250 μm.

    15. The method of claim 1, wherein the layer thickness of the material layer is 1 to 500 μm.

    16. The method of claim 1, wherein the proportion of the binder material is preferably less than 20 volume percent.

    17. The method of claim 1, wherein the particle layer, after the liquid is removed, is about 50% to 80% of the solid density of the particulate material.

    18. The method of claim 1, wherein the further process steps are selected from heat treatment and sintering.

    19. The method of claim 1, wherein the method is carried out in an exchangeable construction container in a batch process or in a continuous process.

    20. The method of claim 1, wherein the slurry is applied horizontally or at an angle of less than 90° to the horizontal construction platform.

    Description

    BRIEF DESCRIPTION OF THE FIGURES:

    [0065] FIG. 1: shows a diagram of a method sequence according to the invention;

    [0066] FIG. 2: shows an illustration of the compression of the particulate feedstock during a method sequence according to the invention;

    [0067] FIG. 3: shows a diagram of a device for carrying out the method according to the invention;

    [0068] FIG. 4: shows devices for applying energy in the method according to the invention;

    [0069] FIG. 5: shows an illustration of the removal of a component.

    REFERENCE NUMERALS

    [0070] 100 Print head

    [0071] 101 Slip application unit

    [0072] 102 Component

    [0073] 103 Energy

    [0074] 104 Lowered layer

    [0075] 105 Building platform

    [0076] 200 Dispersion medium

    [0077] 201 Sinterable and unsinterable particles

    [0078] 202 Binder particles

    [0079] 203 Sintering bridges

    [0080] 204 Adhesive bridges

    [0081] 300 Stirrer

    [0082] 301 Pump

    [0083] 400 Fan

    [0084] 401 Radiation source

    [0085] 402 Positioning unit

    [0086] 500 Rinsing nozzle

    [0087] 501 Solvent jet

    [0088] 502 Particulate material cake