Method and system for additive manufacturing with powder material

Patent metadata

Field	Value
Publication number	US-11400516-B2
Application number	US-201816495407-A
Country	US
Kind code	B2
Filing date	Mar 20, 2018
Priority date	Mar 20, 2017
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

A method for producing a three-dimensional model via additive manufacturing includes building a green block in a layerwise manner with a powder material and a solidifiable non-powder material. The green block includes a green usable model. The solidified non-powder material is removed from the green block to extract the green usable model from the green block and the density of the green usable model is increased by applying Cold Isostatic Pressing (CIP). The green usable model is then sintered to produce a three-dimensional model.

First claim

What is claimed is:

1. A method for producing a three-dimensional model via additive manufacturing, the method comprising:
building a green block in a layerwise manner with a powder material and a solidifiable non-powder material based on an additive manufacturing process, the green block including a green usable model;
removing the solidified non-powder material from the green block to extract the green usable model from the green block;
applying Cold Isostatic Pressing (CIP) after completing the building of the green block, wherein the CIP is configured to increase the density of the powder material forming the green usable model; and
sintering the green usable model to produce a three-dimensional model;
wherein the CIP is applied to the green usable model after extraction from the green block.

2. The method of claim 1 , wherein the CIP is also applied to the green block including the green usable model before the extraction.

3. The method of claim 1 , wherein the green usable model is a green compact of a usable model.

4. The method of claim 1 , wherein the step of building a green block in a layerwise manner is performed via an additive manufacturing system configured to build a layer by (1) printing a pattern with a solidifiable non-powder material to trace the contour of the green usable model; (2) dispensing and spreading a powder material over said pattern; and (3) compacting the powder layer with said pattern.

5. The method of claim 1 , wherein the powder material is selected from an alloy powder, a pure metal powder, a ceramic powder, a polymeric powder, and any combination or mixture thereof.

6. The method of claim 5 , wherein the powder material is an aluminum alloy.

7. The method of claim 1 , wherein said solidifiable non-powder material is a solidifiable ink selected from photocurable inks, wax, thermal inks and any combination thereof.

8. The method of claim 1 , wherein the step of removing the solidified non-powder material from the green block is made by heating the green block to melt, burn or evaporate the solidified non-powder material.

9. The method of claim 1 , wherein the green block also includes green support elements and wherein the green usable model is extracted from the green block by removing the green support elements.

10. The method claim 2 , wherein applying a CIP to the green block comprises inserting the green block into a wet-bag, optionally removing the air from the wet-bag, placing the wet-bag into a CIP chamber, and applying an isostatic pressure to the wet-bag comprising the green block.

11. The method of claim 10 , wherein the isostatic pressure is up to 2,500 bar.

12. The method of claim 3 , wherein applying a CIP to the green usable model after extraction from the green block comprises inserting the green usable model into a wet-bag together with a cushioning material, optionally removing air from the wet bag, placing the wet-bag into a CIP chamber, and applying an isostatic pressure to the wet-bag comprising the green usable model.

13. The method of claim 12 , wherein the isostatic pressure is applied in two steps, wherein the first step comprises applying a first isostatic pressure sufficient to melt the cushioning material to make it flow within the hollow structure of the green usable model, and the second step comprises applying a second isostatic pressure to compact the green usable model.

14. The method of claim 13 , wherein the cushioning material is powdered wax, the first isostatic pressure is up to 50 bar and the second isostatic pressure is up to 2,600 bar.

15. The method according to claim 1 , wherein a temperature applied during the CIP is 40° C.

16. A method for producing three-dimensional models via additive manufacturing, said method comprising:
building a green block in a layerwise manner with a powder material and a solidifiable non-powder material, said green block including one or more green compacts of a usable model and one or more green compacts of support elements, wherein the usable models and the support elements are delimited by patterning lines formed by selective deposition of the solidifiable non-powder material;
applying CIP to the green block after completing the building of the green block, wherein the CIP is configured to increase the density of the powder material forming the one or more green compacts;
heating the green block to remove the solidified non-powder material;
extracting the one or more green compacts of a usable model from the green block by removing the one or more green compacts of support elements; and
sintering the one or more green compacts of a usable model to produce three-dimensional models.

17. A method for producing three-dimensional models via additive manufacturing, said method comprising:
building a green block in a layerwise manner with a powder material and a solidifiable non-powder material, said green block including one or more green compacts of a usable model and one or more green compacts of support elements, wherein the usable models and the support elements are delimited by patterning lines formed by selective deposition of the solidifiable non-powder material;
applying a first CIP to the green block after completing the building of the green block, wherein applying the first CIP is configured to increase the density of the powder material forming the one or more green compacts;
heating the green block to remove the solidified non-powder material;
extracting the one or more green compacts of a usable model from the green block by removing the one or more green compacts of support elements;
further increasing the density of the one or more green compacts of a usable model by applying a second CIP to said one or more green compacts after their extraction from the green block;
sintering the one or more green compacts of a usable model to produce three-dimensional models.

18. A method for producing three-dimensional models via additive manufacturing, said method comprising:
building a green block in a layerwise manner with a powder material and a solidifiable non-powder material, said green block including one or more green compacts of a usable model and one or more green compacts of support elements, wherein the usable models and the support elements are delimited by patterning lines formed by selective deposition of the solidifiable non-powder material;
heating the green block to remove the solidified non-powder material;
extracting the one or more green compacts of a usable model from the green block by removing the one or more green compacts of support elements;
applying a CIP to said one or more green compacts after their extraction from the green block, wherein applying the CIP is configured to increase the density of the powder material forming the one or more green compacts;
sintering the one or more green compacts of a usable model to produce three-dimensional models.

19. A method for increasing the density of a green usable model, said method comprising inserting said green usable model into a wet-bag together with a cushioning material, optionally removing the air from the wet bag, placing said wet-bag into a CIP chamber, and applying an isostatic pressure to said wet-bag to increase the density of said green usable model;
wherein the isostatic pressure is applied in two steps, wherein the first step comprises applying a first isostatic pressure sufficient to melt the cushioning material and make it flow within hollow structures of the green usable model, and the second step comprises applying a second

Assignees

• Stratasys Ltd

Inventors

• Sheinman Yehoshua
• Hirsch Shai

Classifications

• B22F3/02 Primary

  Compacting only · CPC title

• B22F10/43

  characterised by material · CPC title

• B22F10/10 Primary

  Formation of a green body · CPC title

• B33Y40/20

  Post-treatment, e.g. curing, coating or polishing · CPC title

• B33Y30/00 Primary

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title