Shell and Core Additive Manufacture

Patent metadata

Field	Value
Publication number	US-2016039006-A1
Application number	US-201414451798-A
Country	US
Kind code	A1
Filing date	Aug 5, 2014
Priority date	Aug 5, 2014
Publication date	Feb 11, 2016
Grant date	—

Abstract

A process for manufacturing a part includes forming a shell by an additive manufacturing process, the shell having an interior surface that defines a cavity therein, filling the cavity with a liquid material, applying a heat transfer fluid to the shell during the filling the cavity with the liquid material, and solidifying the liquid material to form a solid core within the shell.

First claim

We claim:

1 . A part manufactured by a process, the process comprising:
forming a metallic shell by additive manufacturing, the metallic shell having an interior surface that defines a cavity therein; filling the cavity with a molten metallic material to form a metallic core within the metallic shell; and effecting a metallurgical bond between the metallic core and the metallic shell, such that the metallic shell composes at least a portion of an external surface of the part.

2 . The part of claim 1 , wherein the process further comprises solidifying the molten metallic material within the metallic shell, and the process does not include separating substantially all of the metallic shell from the metallic core after the solidifying the molten metallic material.

3 . The part of claim 1 , wherein the process further comprises filling pores within a wall of the metallic shell with the molten metallic material in addition to the filling the cavity with the molten metallic material.

4 . The part of claim 1 , wherein the interior surface of the metallic shell is substantially impermeable to the molten metallic material.

5 . The part of claim 2 , wherein a material of the metallic shell is selected from the group consisting of stainless steel, TiA16V4, maraging steel, and carbide-containing alloys.

6 . The part of claim 1 , wherein the metallic shell further comprises a support structure disposed within the cavity.

7 . The part of claim 1 , wherein a material of the metallic core is selected from the group consisting of tin alloys, bismuth alloys, tin and bismuth alloys, cast steel, ductile iron, brass, bronze, and aluminum.

8 . The part of claim 1 , wherein a material of the metallic shell is different from a material of the metallic core.

9 . The part of claim 8 , wherein a hardness of the material of the metallic shell is greater than a hardness of the material of the metallic core.

10 . The part of claim 8 , wherein a ductility of the material of the metallic core is greater than a ductility of the material of the metallic shell.

11 . The part of claim 8 , wherein the cavity does not include voids having a characteristic dimension that is less than one hundred times a characteristic dimension of pores defined within a wall of the metallic shell.

12 . The part of claim 1 , wherein the process further comprises applying a heat transfer medium to the metallic shell during the filling the cavity with the molten metallic material.

13 . A process for manufacturing a part, comprising:
forming a shell by an additive manufacturing process, the shell having an interior surface that defines a cavity therein; filling the cavity with a liquid material; applying a heat transfer fluid to the shell during the filling the cavity with the liquid material; and solidifying the liquid material to form a solid core within the shell.

14 . The process of claim 13 , wherein the shell is metallic.

15 . The part of claim 14 , wherein the liquid material comprises a polymer-based resin.

16 . The process of claim 13 , wherein the shell composes at least a portion of a final exterior surface of the part.

17 . The process of claim 13 , wherein the liquid material is a molten metallic material.

18 . The process of claim 13 , wherein the applying a heat transfer fluid to at least a portion of the shell is accomplished by at least one of immersing the shell in the heat transfer fluid, spraying the heat transfer fluid onto the shell, and fixture quenching the shell using the heat transfer fluid.

19 . A method for manufacturing a part comprising the steps of:
forming a metallic shell by additive manufacturing, the metallic shell having an interior surface that defines a cavity therein; filling the cavity with a molten metallic material to form a metallic core within the metallic shell; and effecting a metallurgical bond between the metallic core and the metallic shell, such that the metallic shell composes at least a portion of an external surface of the part.

20 . The method of claim 19 , further comprising applying a heat transfer fluid to at least a portion of the metallic shell during the filling the cavity with the molten metallic material.

Assignees

• Caterpillar Inc

Inventors

• Amstutz Aaron
• Marchione Thierry

Classifications

• B22D19/00

  Casting in, on, or around objects which form part of the product (B22D23/04 takes precedence; alumino-thermic welding B23K23/00; coating by casting molten material on the substrate C23C6/00) · CPC title

• B32B15/01

  all layers being exclusively metallic {(making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00)} · CPC title

• B32B15/012 Primary

  one layer being formed of an iron alloy or steel, another layer being formed of aluminium or an aluminium alloy · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B29C33/40

  Plastics, e.g. foam or rubber · CPC title