Additive manufacturing of functionally gradient degradable tools

1. A method of manufacturing an article, the method comprising:

depositing a metallic powder on a substrate or a worktable;

fusing the metallic powder according to a preset pattern; and

adjusting a composition of the metallic powder or a condition to fuse the metallic powder or a combination thereof to additively form an article such that the article has a first portion and a second portion, wherein the first portion has one or more of the following properties different than those of the second portion: corrosion rate; tensile strength; compressive strength; modulus; or hardness,

wherein the metallic powder comprises a coated particle having a particle core with a nanoscale coating disposed thereon, the nanoscale coating having a melting point different than a melting point of the particle core.

2. The method of claim 1 , wherein the depositing and the fusing are carried out as part of a selective laser sintering process, a laser melting process, or a direct metal deposition process.

3. The method of claim 1 , wherein fusing the metallic powder comprises applying an energy beam from an energy source to the metallic powder.

4. The method of claim 1 , wherein the metallic powder is at least partially fused before deposited on the substrate or the worktable.

5. The method of claim 1 , wherein the metallic powder is fused after deposited on the substrate or the worktable.

6. The method of claim 1 , wherein the particle core comprises one or more of the following: Mg; Al; Zn; Mn, or an alloy thereof.

7. The method of claim 1 , wherein the nanoscale coating comprises one or more of the following: Al; Zn; Mn; Mg; Mo; W; Cu; Fe; Si; Ca; Co; Ta; Re; or Ni; an oxide thereof; a carbide thereof; or a nitride thereof.

8. The method of claim 1 , wherein adjusting a condition to fuse the metallic powder comprises fusing the metallic powder at an energy gradient.

9. The method of claim 1 , wherein the metallic powder further comprises a second particle that is compositionally different from the coated particle.

10. The method of claim 9 , wherein the second particle comprises one or more of the following: Fe; Ni; Co; W; or Cu; or oxides; nitrides; or carbides thereof.

11. The method of claim 9 , wherein adjusting a composition of the metallic powder comprises changing the relative amounts of the coated particle and the second particle.

12. The method of claim 9 , wherein adjusting a composition of the metallic powder comprises varying a particle size of the metallic matrix particle, varying a particle size of the second particle, or a combination thereof.

13. A method of using an article, the method comprising:

forming an article according to a method of claim 1 , the article comprising a first portion that is corrodible in a fluid at a first corrosion rate and a second portion that is corrodible in the fluid at a second corrosion rate, wherein the first corrosion rate is greater than the second corrosion rate;

using the article to perform a first operation;

exposing the article to the fluid;

selectively corroding the first portion of the article to provide a corroded article; and

using the corroded article to perform a second operation that is different from the first operation.

14. The method of claim 13 , wherein the article is a downhole article, the fluid is a wellbore fluid, and the first and second operations are wellbore operations.

15. A method of manufacturing an article, the method comprising:

depositing a metallic powder on a substrate or a worktable;

fusing the metallic powder according to a preset pattern; and

adjusting a composition of the metallic powder or a condition to fuse the metallic powder or a combination thereof to additively form an article such that the article has a first portion and a second portion, wherein the first portion has one or more of the following properties different than those of the second portion: corrosion rate; tensile strength; compressive strength; modulus; or hardness;

wherein the metallic powder comprises an uncoated metallic matrix particle and a second particle;

the metallic matrix particle comprising one or more of the following: a magnesium-based alloy; an aluminum-based alloy; or a zinc-based alloy; and

the second particle comprising one or more of the following: a metal; an oxide of the metal; a nitride of the metal; or a cermet of the metal; wherein the metal is W; Co; Cu; Ni; or Fe.

16. The method of claim 15 , wherein adjusting a composition of the metallic powder comprises changing the relative amounts of the metallic matrix particle and the second particle.

17. The method of claim 16 , wherein adjusting a composition of the metallic powder comprises varying a particle size of the metallic matrix particle, varying a particle size of the second particle, or a combination thereof.

18. The method of claim 15 , wherein the metallic matrix particle comprises a magnesium-based alloy.

19. The method of claim 15 , wherein the metallic matrix particle comprises a zinc-based alloy.