Powder monitoring

Patent metadata

Field	Value
Publication number	US-2019329300-A1
Application number	US-201916510180-A
Country	US
Kind code	A1
Filing date	Jul 12, 2019
Priority date	Oct 27, 2015
Publication date	Oct 31, 2019
Grant date	—

Abstract

A method including filling an internal passage of an additively manufactured (AM) article with a state change fluid, causing the state change fluid to change from a first state having a first viscosity to a second state that is either solid or has a second viscosity that is higher than the first viscosity within the internal passage, causing the state change fluid to change back from the second state to the first state, removing residual powder from the additively manufactured article by flushing the state change fluid from the internal passage, measuring electrical impedance of a piezoelectric wafer connected to the additively manufactured article, and determining that more than a threshold amount of residual powder remains within the AM article based on the measured electrical impendence of the additively manufactured article being outside of a selected range from an expected impendence value.

First claim

What is claimed is:

1 . A method, comprising:
filling an internal passage of an additively manufactured (AM) article with a state change fluid; and causing the state change fluid to change from a first state having a first viscosity to a second state that is either solid or has a second viscosity that is higher than the first viscosity within the internal passage; causing the state change fluid to change back from the second state to the first state; removing residual powder from the additively manufactured article by flushing the state change fluid from the internal passage; measuring electrical impedance of a piezoelectric wafer connected to the additively manufactured article; and determining that more than a threshold amount of residual powder remains within the AM article based on the measured electrical impendence of the additively manufactured article being outside of a selected range from an expected impendence value.

2 . The method of claim 1 , further comprising evaluating a dynamic response as compared to the expected value.

3 . The method of claim 1 , wherein the additively manufactured article (AM) is placed in service if the measured impedance of the additively manufactured article (AM) is within the acceptable range.

4 . The method of claim 1 , wherein the expected value is based on an electrical impedance of a clean part.

5 . A method, comprising:
measuring electrical impendence of an article using an impendence evaluator; comparing the measured electrical impendence of the article to an expected impendence value; and removing residual powder from the article an internal passage of the article if the measured impendence of the additively manufactured article is outside of a selected threshold of the expected impendence value.

6 . The method of claim 5 , wherein the article is an additively manufactured article.

7 . The method of claim 5 , wherein measuring electrical impendence uses an piezoelectric wafer.

8 . The method of claim 5 , wherein removing material includes removing residual powder.

9 . The method of claim 5 , further comprising flushing the internal passage in order to remove the residual material.

10 . The method of claim 5 , further comprising placing the additively manufactured article in service if the measured impedance of the additively manufactured article is within the acceptable range.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Fennessy Colette O
• Reynolds Shawn K

Classifications

• B22F3/24 Primary

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

• B08B3/10

  with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration · CPC title

• B22F10/20

  Direct sintering or melting · CPC title

• B22F10/68

  Cleaning or washing · CPC title

• B29C64/35

  Cleaning · CPC title