Additive Manufacturing Methods

Patent metadata

Field	Value
Publication number	US-2016354976-A1
Application number	US-201514733582-A
Country	US
Kind code	A1
Filing date	Jun 8, 2015
Priority date	Jun 8, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

An additive manufacturing method includes using hydrogenated titanium in forming an object by additive manufacturing, the object having a first microstructure. The method includes heat treating the hydrogenated titanium and, after completing a shape of the object, dehydrogenating the object. The dehydrogenated object has a second microstructure different from the first microstructure. Also, another additive manufacturing method includes
forming an object containing Ti-6Al-4V, the object having a first microstructure containing columnar structures along a build direction of the additive manufacturing and the object exhibiting mechanical property anisotropy resulting from the columnar structures. After completing a shape of the object, the method includes hydrogenating the Ti-6Al-4V, heat treating the object containing the hydrogenated titanium, and dehydrogenating the heat treated object. The method reduces mechanical property anisotropy and the dehydrogenated object has a second microstructure different from the first microstructure.

First claim

What is claimed is:

1 . An additive manufacturing method comprising:
using hydrogenated titanium in forming an object by additive manufacturing, the object having a first microstructure; heat treating the hydrogenated titanium; and after completing a shape of the object, dehydrogenating the object, the dehydrogenated object having a second microstructure different from the first microstructure.

2 . The method of claim 1 wherein the use of hydrogenated titanium comprises hydrogenating additive titanium using hydrogen-containing gas while adding titanium to the object.

3 . The method of claim 2 wherein the hydrogen-containing gas comprises H 2 .

4 . The method of claim 1 wherein the use of hydrogenated titanium comprises using additive manufacturing titanium feedstock containing hydrogen.

5 . The method of claim 4 wherein the feedstock comprises titanium hydride powder.

6 . The method of claim 4 wherein the feedstock comprises titanium wire containing diffused hydrogen or titanium alloy wire containing diffused hydrogen.

7 . The method of claim 1 wherein the heat treating occurs between about 500 and about 1,200° C.

8 . The method of claim 1 wherein the heat treating occurs while adding titanium to the object.

9 . The method of claim 8 wherein the heat treating comprises melting additive manufacturing titanium feedstock while hydrogenating additive titanium using hydrogen-containing gas and while adding hydrogenated titanium to the object.

10 . The method of claim 1 wherein the heat treating occurs after completing the shape of the object and before the dehydrogenating.

11 . The method of claim 1 further comprising cooling the object after the heat treating and after completing the shape of the object, but before the dehydrogenating.

12 . The method of claim 1 wherein the completed shape comprises about 0.5 to about 1.2 weight % hydrogen before the dehydrogenating.

13 . The method of claim 1 wherein the dehydrogenated object comprises titanium alloyed with aluminum and vanadium.

14 . The method of claim 1 wherein the second microstructure exhibits finer structure compared to the first microstructure.

15 . An additive manufacturing method comprising:
using titanium, titanium hydride, aluminum, and vanadium additive manufacturing feedstock in forming an object by additive manufacturing, the object having a first microstructure; after completing a shape of the object, heat treating the object; cooling the heat treated object; and dehydrogenating the cooled object, the dehydrogenated object having a second microstructure exhibiting finer and more uniform structure compared to the first microstructure.

16 . The method of claim 15 wherein the heat treating occurs between about 600 and about 1,000° C.

17 . The method of claim 15 wherein the completed shape comprises about 0.6 to about 1 weight % hydrogen before the dehydrogenating.

18 . The method of claim 15 wherein the dehydrogenated object comprises titanium alloyed with aluminum and vanadium.

19 . The method of claim 18 wherein the titanium alloyed with aluminum and vanadium comprises Ti-6Al-4V.

20 . An additive manufacturing method comprising:
forming an object containing Ti-6Al-4V by additive manufacturing, the object having a first microstructure containing columnar structures along a build direction of the additive manufacturing and the object exhibiting mechanical property anisotropy resulting from the columnar structures; after completing a shape of the object, hydrogenating the Ti-6Al-4V using hydrogen-containing gas; heat treating the object containing the hydrogenated titanium; and dehydrogenating the heat treated object and reducing mechanical property anisotropy, the dehydrogenated object having a second microstructure different from the first microstructure.

Assignees

• Boeing Co

Inventors

• Zhang Hao
• Quarberg Ryan P

Classifications

• B22F3/1007 Primary

  Atmosphere (B22F3/1021 takes precedence) · CPC title

• B22F10/64

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

• B22F10/25

  Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS] · CPC title

• B22F10/38

  to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures · CPC title

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title