METHODS FOR SHAPING HIGH ASPECT RATIO ARTICLES FROM METALLIC GLASS ALLOYS USING RAPID CAPACITIVE DISCHARGE AND METALLIC GLASS FEEDSTOCK FOR USE IN SUCH METHODS

• US 20150197837A9
• Filed: 03/17/2014
• Published: 07/16/2015
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Glassimetal Technology Inc.
• Inventors: Schramm, Joseph P., Na, Jong Hyun, Demetriou, Marios D., Lee, David S., Johnson, William L.
• Granted Patent: US 9,845,523 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61L 27/04 Metals or alloys
• CPC Class Codes: C21D 1/40 Direct resistance heating
• CPC Class Codes: C21D 2201/03 Amorphous or microcrystalline structure
• CPC Class Codes: C22B 4/06 Alloys C22B4/005 takes precedence
• CPC Class Codes: C22C 1/11 Making amorphous alloys
• CPC Class Codes: C22C 45/00 Amorphous alloys making amorphous non-ferrous alloys C22C1/11
• CPC Class Codes: C22C 45/001 with Cu as the major constituent
• CPC Class Codes: C22C 45/04 with nickel or cobalt as the major constituent
• CPC Class Codes: C22F 1/002 by rapid cooling or quenching; cooling agents used therefor
• CPC Class Codes: C22F 1/10 of nickel or cobalt or alloys based thereon

Abstract

The disclosure is directed to a method of forming high-aspect-ratio metallic glass articles that are substantially free of defects and cosmetic flaws by means of rapid capacitive discharge forming. Metallic glass alloys that are stable against crystallization for at least 100 ms at temperatures where the viscosity is in the range of 10⁰ to 10⁴ Pa-s are considered as suitable for forming such high-aspect-ratio articles.

Claims

1. A method of forming an article from a metallic glass alloy, the method comprising:

applying a quantum of electrical energy to the feedstock using a rapid capacitive discharge forming system to heat the feedstock to a temperature above the glass transition where the viscosity of the metallic glass alloy is in the range of 10⁰ to 10⁴ Pa-s, wherein the feedstock comprising a metallic glass alloy having a uniform cross-section, the metallic glass alloy being capable of resisting crystallization for at least 100 ms at a temperature above the glass transition at said viscosity;

shaping the heated feedstock into an article having an aspect ratio of at least 10; and

cooling the shaped article to a temperature below the glass transition temperature of the metallic glass alloy sufficiently fast to avoid crystallization of the metallic glass.

2. A method according to claim 1, where the article has thickness of 2 mm or less.

3. A method according to claim 1, wherein the article thickness is from 0.5 mm to 2 mm.

4. The method of claim 1, wherein the viscosity is from 10¹ to 10³ Pa-s.

5. The method of claim 1, wherein the viscosity is from 10² to 10⁴ Pa-s.

6. A method according to claim 1, wherein said shaping is subsequent to said applying.

7. A method according to claim 1, wherein the shaping is selected from molding, forging, and casting.

8. The method of claim 1, wherein the metallic glass alloy composition is Zr—

based, Ti—

based, Ta—

based, Y-based, Hf-based, Ni—

based, Pd-based, Pt-based, Fe-based, Ni—

based, Co-based, Cu-based, Au-based, Al-based, La-based, Ce-based, Pr-based, Nd-based, Gd-based, Mg-based, or Ca-based metallic glass alloy.

9. The method of claim 1, wherein the metallic glass alloy comprises the formula X_100-a-b Y_aZ_b, wherein

X is Ni, Fe, Co or a combination thereof,

Y is Cr, Mo, Mn, Nb, Ta or a combination thereof,

Z is P, B, C, Si, Ge or a combination thereof,

a is between 5 and 15 atomic %, and

b is between 15 and 25 atomic %.

10. The method of claim 1, wherein the metallic glass alloy is selected from a Ni—

Cr—

Nb—

P—

B, Ni—

Cr—

Ta—

P—

B, Ni—

Cr—

Mn—

P—

B, Ni—

Mo—

Nb—

Mn—

P—

B, Ni—

Mn—

Nb—

P—

B, Ni—

Cr—

Mo—

Si—

B—

P, and Ni—

Fe—

Si—

B—

P metallic glass alloy.

11. The method of claim 1, wherein the metallic glass alloy comprises the formula Ni_100-a-b-c-d X_aY_bP_cZ_d, wherein

X is Cr, Mo, Mn or combinations thereof

Y is Nb, Ta, Mn or combinations thereof

Z is B, Si or combinations thereof

a is between 3 and 15 atomic %

b is between 1 and 6 atomic %

c is between 12 and 20 atomic %

d is between 0.5 and 6 atomic %

12. The method of claim 1, wherein the metallic glass alloy crystallizes at a temperature T_x that is at least 45°

C. higher than its glass transition temperature T_g when heated by a constant heating rate of 0.67°

C./s.

14. The method of claim 1, wherein the viscosity is from 10¹ to 10³ Pa-s.

15. The method of claim 1, wherein the viscosity is from 10² to 10⁴ Pa-s.

17. A high aspect ratio metallic glass article produced by the process according to claim 1.

13. A method of assessing a metallic glass alloy for use in forming a high aspect ratio metallic glass article using the RCDF method, comprising:

applying a quantum of electric energy to a sample of the metallic glass alloy to heat the sample to a temperature above the glass transition temperature, where the viscosity of the metallic glass is between 10⁰-10⁴ Pa-s;

monitoring the temperature of the sample to determine the time at which the sample crystallizes by releasing the crystallization enthalpy;

identifying the metallic glass alloy as suitable for forming high aspect ratio articles when the time to crystallization is greater than or equal to 100 ms.

16. A high aspect ratio metallic glass article that is capable of resisting crystallization for at least 100 ms at a temperature above the glass transition where the viscosity of the metallic glass alloy forming said article is between 10⁰-10⁴ Pa-s, said metallic glass alloy selected from Ni_68.17Cr_8.65Nb_2.98P_16.42B_3.28Si_0.5, Ni_68.17Cr_8.65Nb_2.98P_15.92B_3.28Si₁, Ni₆₉Cr₁₀Nb_1.5P₁₈B_1.5, Ni₆₉Cr_9.5Nb₂P_17.5B₂, Ni₆₉Cr₉Nb_2.5P₁₇B_2.5, Ni₆₉Cr₈Nb_3.5P₁₆B_3.5, Ni₆₉Cr_7.5Nb₄P_15.5B₄, Ni₆₉Cr₇Nb_4.5P₁₅B_4.5, Ni₆₉Cr_8.75Nb_2.75P₁₆B_3.5, Ni₆₉Cr₉Nb_2.5P_15.5B₄, Ni₆₉Cr_9.25Nb_2.25P₁₅B_4.5, Ni₆₉Cr_9.5Nb₂P_14.5B₅, Ni₆₉Cr_9.75Nb_1.75P₁₄B_5.5, Ni₆₉Cr₁₀Nb_1.5P_13.5B₆, Ni_67.5Co_1.5Cr_8.5Nb₃P_16.5B₃, Ni₆₆Co₃Cr_8.5Nb₃P_16.5B₃, Ni₆₄Co₅Cr_8.5Nb₃P_16.5B₃, Ni₅₉Co₁₀Cr_8.5Nb₃P_16.5B₃, Ni₅₄Co₁₅Cr_8.5Nb₃P_16.5B₃, Ni₄₉Co₂₀Cr_8.5Nb₃P_16.5B₃, Ni₄₄Co₂₅Cr_8.5Nb₃P_16.5B₃, Ni_61.4Co₁₀Cr_5.52Nb_3.38P_16.67B_3.03, Ni_56.4Co₁₅Cr_5.52Nb_3.38P_16.67B_3.03, Ni_51.4Co₂₀Cr_5.52Nb_3.38P_16.67B_3.03, Ni_46.4Co₂₅Cr_5.52Nb_3.38P_16.67B_3.03, Ni_67.1Cr₁₀Nb_3.4P₁₈Si_1.5, Ni_66.1Cr₁₁Nb_3.4P₁₈Si_1.5, Ni_64.1Cr₁₃Nb_3.4P₁₈Si_1.5, Ni_62.1Cr₁₅Nb_3.4P₁₈Si_1.5, Ni_68.5Cr_8.5Mn₃P₁₇B₃, Ni_68.5Cr_7.5Mn₃Mo₁P_16.5B₃, Ni_68.5Cr₉Ta₃P_16.5B₃, Ni_68.5Cr₉Ta₃P_16.25B_3.25, Ni_68.5Cr₉Ta₃P₁₆B_3.5, Ni_68.5Cr₉Ta₃P_15.5B₄, Ni_68.5Cr₉Ta₃P₁₅B_4.5, Ni_69.5Cr₈Ta₃P_16.25B_3.25, Ni_68.5Cr₉Ta₃P_16.25B_3.25, Ni_67.5Cr₁₀Ta₃P_16.25B_3.25, Ni_68.5Cr₁₀Ta₂P_16.25B_3.25, Ni_68.5Cr_9.5Ta_2.5P_16.25B_3.25, and Ni_68.5Cr_8.5Ta_3.5P_16.25B_3.25.

18. The article of claim 16, where the body of the article has a thickness of 2 mm or less.

19. The article of claim 16, where the body of the article has a thickness in the range of 0.5 to 2 mm.

20. The article of claim 16, wherein the article is a component of a consumer electronics device, a medical implant, a dental prosthetic, a watch component, a ferromagnetic core, a sporting good, or a luxury good.