EP-4737033-A1 - AN APPARATUS FOR POWDER-BASED ADDITIVE MANUFACTURING OF THREE-DIMENSIONAL STRUCTURES

EP4737033A1EP 4737033 A1EP4737033 A1EP 4737033A1EP-4737033-A1

Abstract

The invention refers to an apparatus for powder-based additive manufacturing of three-dimensional structures on a platform (4). The apparatus comprises a powder delivery mechanism (100) with a first powder chamber (11) for a first powder with a first powder outlet, and a second powder chamber (12) for a second powder with a second powder outlet. In addition, the powder delivery mechanism (100) comprises a gating mechanism (3) with a first slot (31) and a second slot (32), wherein the powder delivery mechanism (100) and/or the platform (4) are rotatable around a platform center axis (10) of the platform (4), wherein the gating mechanism (3) is arranged such that the first slot (31) defines an outlet surface of the first powder outlet and the second slot (32) defines an outlet surface of the second powder outlet, wherein the gating mechanism (3) is displaceable relatively to the first powder outlet and/or the second powder outlet.

Inventors

BAMBACH, MARKUS
TUCKER, MICHAEL
STEFFEN, Raphael
PIRCHL, Dion

Assignees

ETH Zurich

Dates

Publication Date: 20260506
Application Date: 20241030

Claims (15)

An apparatus for powder-based additive manufacturing of three-dimensional structures on a platform (4), comprising a powder delivery mechanism (100) comprising • a first powder chamber (11) for a first powder with a first powder outlet, • a second powder chamber (12) for a second powder with a second powder outlet, and • a gating mechanism (3) with a first slot (31) and a second slot (32), wherein the powder delivery mechanism (100) and/or the platform (4) are rotatable around a platform center axis (10) of the platform (4), wherein the gating mechanism (3) is arranged such that the first slot (31) defines an outlet surface of the first powder outlet and the second slot (32) defines an outlet surface of the second powder outlet, wherein the gating mechanism (3) is displaceable relatively to the first powder outlet and/or the second powder outlet.
The apparatus according to claim 1, comprising further a decoupling mechanism (2) arranged between the first (11) and/or second (12) powder chamber and the respective first and/or second powder outlet, wherein the decoupling mechanism (2) is adapted to control the powder flux from the first (11) and/or second (12) powder chamber to the respective first and/or second powder outlet.
The apparatus according to claim 2, wherein the decoupling mechanism (2) comprises a first duct (21) connecting the first powder chamber (11) with the first powder outlet, and/or a second duct (22) connecting the second powder chamber (12) with the second powder outlet.
The apparatus according to claim 3, wherein a smallest angle (α) between a center axis of the first duct (21) and the center axis (10) of the platform (4) is 20° ≤ α ≤ 70° and/or wherein a smallest angle (β) between a center axis of the second duct (22) and the platform center axis (10) is between 20° ≤ β ≤ 70°.
The apparatus according to claim 3, wherein a valve and/or slotted wheel is arranged in the first (21) and/or second (22) duct.
The apparatus according to one of the preceding claims, wherein the first slot (31) and the second slot (32) of the gating mechanism (3) are aligned at one edge with a shortest distance (d) of 0mm ≤ d ≤ 5mm, in particular 0.5mm ≤ d ≤ 5mm, in particular, wherein the distance (d) lies on a circular line of a circle around the platform center axis (10).
The apparatus according to one of the preceding claims, wherein the powder delivery mechanism (100) further comprises • a front blade (51) arranged before the gating mechanism (3) in a rotation direction around the platform center axis (10) and/or • a rear blade (52) arranged behind the gating mechanism (3) in the rotation direction, in particular, wherein a blade distance between the platform (4) and the rear blade (52) is adjustable such that the blade distance defines a height of a powder bed in the intended use of the apparatus.
The apparatus according to one of the preceding claims, wherein first slot (31) and the second slot (32) are arranged such that in the intended use of the apparatus, the first powder releasing from the first slot (31) forms a first powder bed on the platform (4) and the second powder releasing from the second slot (32) forms a second powder bed on the platform (4) adjacent to the first powder bed in radial direction of the platform (4) .
The apparatus according to one of the preceding claims, wherein the platform (4) is movable relatively to the powder delivery mechanism (100) in vertical direction.
The apparatus according to one of the preceding claims wherein the gating mechanism (3) comprises a material selector (53) such that in the intended use of the apparatus, the material selector (53) separates the first and second powder that release through the first slot (31) respectively through the second slot (32) to the platform (4), in particular, wherein a motor controls the material selector (53) to slide and/or bend the material selector (53).
The apparatus according to one of the preceding claims, wherein the gating mechanism (3) comprises a mask (6) to partially cover the first (31) and or the second (32) slot.
A powder delivery mechanism (100) for an apparatus according to one of the preceding claims.
A gating mechanism (3) for a powder delivery mechanism according to claim 12.
A Method to manufacture three-dimensional structures on a platform (4) with an apparatus according to claim 1 to 11 comprising: • rotating the powder delivery mechanism (100) and/or the platform (4) around the platform center axis (10), • releasing the first powder and/or the second powder through the first slot (31) and the second slot (32) respectively to form a first powder bed of first powder and/or a second powder bed of second powder, • exposing the first and/or second powder bed to an energy source to fuse a specific area of the first and/or second powder bed.
Method according to claim 14 comprising: • moving the platform (4) relatively to the powder delivery mechanism (100) in vertical direction in a linear motion or in incremental steps.

Description

Technical Field The invention refers in a first aspect to an apparatus for powder-based additive manufacturing of three-dimensional structures, in a second aspect to a powder delivery mechanism for the apparatus, in a third aspect to a gating mechanism for the powder delivery mechanism and in a fourth aspect to a method to manufacture three-dimensional structures with the apparatus. Background Art Additive manufacturing enables the production of highly performant parts due to the high degree of design freedom they afford. To enable and accelerate the manufacturing of round or circular shaped parts, rotational additive manufacturing machines exist, which deposit material in a circular, continuous manner, while the deposited material remains stationary. Following the deposition of the powder material, a laser selectively joins material for the additive manufacturing process. Certain circular shaped parts like nozzles, bearings, bushings, impellers, or heat exchangers, would benefit from the use of multiple materials, whereby the material properties can be locally varied based on the specific application. With existing processes, such multi-material composite parts would require multiple manufacturing steps. This adds significant cost and manufacturing time to these parts. Disclosure of the Invention Therefore, the problem to be solved by the present invention is to provide an apparatus to manufacture roughly axisymmetric or circular shaped parts made of multiple materials. The apparatus should comprise a powder deposition system that allows for the selective deposition of multiple materials (metals, polymers, or ceramics) wherein the rapid deposition process enables accelerated manufacturing. In addition, the material should be deposited adjacent to one another, to enable the additive manufacturing of composite /multi-materials. This problem is solved by present in a first aspect referring to an apparatus for powder-based additive manufacturing of three-dimensional structures, in a second aspect to a powder delivery mechanism for the apparatus, in a third aspect to a gating mechanism for the powder delivery mechanism and in a fourth aspect to a method to manufacture three-dimensional structures with the apparatus. The first aspect of the invention refers to the apparatus for powder-based additive manufacturing of three-dimensional structures on a platform. The apparatus comprises a powder delivery mechanism comprising a first powder chamber for a first powder, wherein the first powder chamber comprises a first outlet. The apparatus comprises further a second powder chamber for a second powder, wherein the second powder chamber comprises a second powder outlet. In a further advantageous embodiment of the invention, the powder delivery mechanism can of course further comprise a third, fourth, fifth or any further powder chamber for a third, fourth, fifth or any further powder, wherein the respective powder chamber comprises a respective powder outlet and is further adjusted to match the powder delivery mechanism. The first respectively the second powder outlet are adapted to release the first respectively second powder from the first respectively second powder chamber during the intended use of the apparatus, when the powder is deposited on the platform. The first and/or second powder is advantageously a metallic powder comprising a material selected from the group consisting of Cu, Ni, Fe, Al, Nb, Mg elemental powders or alloys and mixtures thereof. Further advantageously, the apparatus can be used to deposit powder combinations e.g., depositing a first powder through the first outlet surface and a second powder through the second outlet surface. If there is a third powder chamber, there can be further a third powder be deposited, such that a first powder, a second powder and a third powder are deposited. In particular, the third powder here might be the same type as the first powder and therefore lead to an alternating deposition of powders. The powder delivery mechanism and/or the platform are rotatable around a platform center axis of the platform. Therefore, the powder delivery mechanism might be rotatable around the platform center axis, but also the platform might be rotatable around the platform center axis, or both are rotatable. Advantageously, the term platform center axis refers to a center axis of the platform, which is the center of the rotational movement of the platform and/or the powder delivery mechanism. Because of the rotational movement of the powder delivery mechanism relatively to the platform, the powder can be deposited during the circular movement of the powder delivery mechanism relatively to the platform and at the same time, the powder can be consolidated with an energy source (e.g. laser, e-beam, microwaves, IR heating) that exposes the deposited material. Compared to a straight movement of the powder delivery mechanism, the rotational movement has the advantage of producing rotati