Dissolving metal supports in 3d printed metals and ceramics using sensitization

Patent metadata

Field	Value
Publication number	US-2019314895-A1
Application number	US-201716317725-A
Country	US
Kind code	A1
Filing date	Feb 16, 2017
Priority date	Jul 15, 2016
Publication date	Oct 17, 2019
Grant date	—

Abstract

Systems and methods are disclosed for fabricating a metal or ceramic component using a 3D printer. An entire 3D printed piece, including both the metal or ceramic component and one or more support structures, is created of a first metal or ceramic material. A sensitization layer is applied to all or part of the 3D printed piece to chemically alter portions of the first metal or ceramic material near the surface making those portions of the material more sensitive to the etching process. The etching process causes the affected material to deplete and separates the component from the support structures without requiring mechanical machining.

First claim

What is claimed is:

1 . A method of fabricating a metal or ceramic component using 3D printing, the method comprising:
creating a 3D printed piece constructed of a first metal or ceramic material and including a body of the component coupled to one or more support structures; applying a sensitization agent to surfaces of the 3D printed piece, wherein the sensitization agent alters a chemical composition of the first metal or ceramic material into a second metal or ceramic material at the surfaces of the 3D printed piece where the sensitization agent was applied such that, after reacting with the sensitization agent, the first metal or ceramic material of the metal or ceramic piece is at least partially covered by the second metal or ceramic material; and separating the body of the component from the one or more support structures by applying a chemical or electrochemical dissolution process that dissolves the second metal or ceramic material without significantly affecting the first metal or ceramic material.

2 . The method of claim 1 , wherein creating the 3D printed piece includes creating a 3D printed piece where a portion of the one or more support structures that contacts the body of the component has a smaller cross-sectional area relative to the body of the component.

3 . The method of claim 1 , further comprising applying a heat treatment process to the 3D printed piece after applying the sensitization agent to facilitate a reaction between the first metal or ceramic material and the sensitization agent that partially converts the first metal or ceramic material to the second metal or ceramic material.

4 . The method of claim 1 , wherein a reaction between the first metal or ceramic material and the sensitization agent that partially converts the first metal or ceramic material to the second metal or ceramic material includes a reaction selected from a group consisting of carburization, nitridation, and leeching.

5 . The method of claim 1 , wherein the first metal or ceramic material includes stainless steel, the second metal or ceramic material includes chromium deficient stainless steel, and the sensitization agent includes an iron alloy.

6 . The method of claim 1 , wherein applying the sensitization agent to the surfaces of the 3D printed piece includes applying the sensitization agent to surfaces of the body of the component and surfaces of a sacrificial interface region coupling the body of the component to the one or more support structures, wherein applying the sensitization agent to the surfaces of the body of the component alters the chemical composition of the first metal or ceramic material into the second metal or ceramic material at the surfaces of the body of the component, and wherein applying the chemical or electrochemical dissolution process includes at least partially dissolving portions of the second metal or ceramic material at the surfaces of the body of the metal or ceramic component.

7 . The method of claim 6 , wherein creating the 3D printed piece includes creating the sacrificial interface region with a cross-sectional area smaller than the cross-sectional area of the body of the component so that, after applying the sensitization agent to surfaces of the 3D printed piece, a greater proportion of the cross-sectional area of the sacrificial interface region is formed of the second metal or ceramic material compared to the cross-sectional area of the body of the component, and wherein applying the chemical or electrochemical dissolution process includes dissolving the second metal or ceramic material at a rate so that the body of the component is separated from the one or more support structures before the body of the component itself is dissolved.

8 . The method of claim 1 , further comprising applying an additive to the 3D printed piece, wherein the additive protects the first metal or ceramic material from the chemical or electrochemical dissolution process.

9 . The method of claim 1 , further comprising applying an additive to the 3D printed piece, wherein the additive makes the second metal or ceramic material more susceptible to the chemical or electrochemical dissolution process.

10 . The method of claim 1 , wherein applying the sensitization agent to surfaces of the 3D printed piece includes applying the sensitization agent only to surfaces of the 3D printed piece at a sacrificial interface region, wherein the sacrificial interface region is separated from the body of the component by a spacer region, and further comprising applying a machining or polishing process to remove the spacer region from the body of the component after separating the body of the metal or ceramic component from the support structure.

11 . The method of claim 1 , wherein creating the 3D printed piece includes
creating a sacrificial interface region with a smaller cross-sectional area than a cross-sectional area of the body of the component, and creating a spacer region between the body of the component and the sacrificial interface region, wherein a cross-sectional area of the spacer region is larger than the cross-sectional area of the sacrificial interface region such that application of the chemical or electrochemical dissolution process causes the body of the component to separate from the one or more support structures at the sacrificial interface region before completely dissolving the spacer region, and the method further comprising applying a machining or polishing process to remove a remaining portion of the spacer region from the body of the component after separating the body of the component from the support structure.

Assignees

• Univ Arizona State
• Penn State Res Found

Inventors

• Hildreth Owen
• Wright David
• Nassar Abdalla
• Simpson Tim
• Lefky Christopher

Classifications

• B22F10/40

  Structures for supporting workpieces or articles during manufacture and removed afterwards · CPC title

• B22F3/24 Primary

  After-treatment of workpieces or articles {(B22F3/1146 takes precedence)} · CPC title

• B22F10/64

  by thermal means (control of energy beam parameters for post heating B22F10/364) · CPC title

• B22F10/66

  by mechanical means · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title