BULK NICKEL-COBALT-BASED GLASSES BEARING CHROMIUM, TANTALUM, PHOSPHORUS AND BORON

• US 20160090644A1
• Filed: 09/30/2014
• Published: 03/31/2016
• Est. Priority Date: 09/30/2014
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Glassimetal Technology Inc.
• Inventors: Na, Jong Hyun, Abarca, Oscar, Crewdson, Chase, Launey, Maximilien, Demetriou, Marios D., Johnson, William L.
• Application Number:
  US14/501,779
• Publication Number:
  US 20160090644A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C22C 1/11 Making amorphous alloys
• CPC Class Codes: C22C 19/05 with chromium
• CPC Class Codes: C22C 19/058 without Mo and W
• CPC Class Codes: C22C 19/07 based on cobalt
• 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

Ni—Co—Cr—Ta—P—B alloys and metallic glasses with controlled ranges are provided. The alloys demonstrate a combination of good glass forming ability, high toughness, and high stability of the supercooled liquid. The disclosed alloys are capable of forming metallic glass rods of diameters at least 3 mm and up to about 8 mm or greater. Certain alloys with good glass forming ability also have high notch toughness approaching 100 MPa m^1/2, and stability of the supercooled liquid approaching 60° C.

Claims

1. An alloy capable of forming a metallic glass represented by the following formula (subscripts denote atomic percentages):

Ni_{(100-a-b-c-d-e)}Co_aCr_bTa_cP_aB_e

where;

a ranges from 0.5 to 40, b ranges from 3 to 11, c ranges from 1.5 to 4, d ranges from 14 to 17.5, and e ranges from 2 to 5, and

wherein the alloy has a critical rod diameter of at least 3 mm.

2. The alloy of claim 1 wherein c is determined by x+y·

b, where x is between 1.5 and 2 and y is between 0.1 and 0.15.

3. The alloy of claim 1 wherein a ranges from 0.5 to 30, b ranges from 8 to 10.5, c ranges from 2.25 to 3.75, d ranges from 15.5 to 17, e ranges from 2.5 to 4, and wherein the critical rod diameter of the alloy is at least 5 mm.

4. The alloy of claim 1 wherein a ranges from 0.5 to 15, b ranges from 8.5 to 10, c ranges from 2.5 to 3.5, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75, and wherein the critical rod diameter of the alloy is at least 6 mm.

5. The alloy of claim 1 wherein a ranges from 0.5 to 30, b ranges from 6 to 8, c ranges from 2 to 3.5, d ranges from 15.5 to 17, e ranges from 2.5 to 4, and wherein the critical rod diameter of the alloy is at least 5 mm.

6. The alloy of claim 1 wherein a ranges from 0.5 to 5, b ranges from 6.5 to 7.5, c ranges from 2.25 to 3.25, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75, and wherein the critical rod diameter of the alloy is at least 6 mm.

7. The alloy of claim 1 wherein the difference between the crystallization temperature Tx and the glass transition temperature Tg, Δ

Tx=Tx−

Tg, measured at heating rate of 20 K/min, is at least 42°

C.

8. The alloy of claim 1 wherein the difference between the crystallization temperature Tx and the glass transition temperature Tg, Δ

Tx=Tx−

Tg, measured at heating rate of 20 K/min, is at least 50°

C.

9. The alloy of claim 1 wherein up to 2 atomic percent of Cr is substituted by Fe, Mn, W, Mo, Ru, Re, Cu, Pd, Pt, or combinations thereof.

10. The alloy of claim 1 wherein up to 2 atomic percent of Ni is substituted by Fe, Mn, W, Mo, Ru, Re, Cu, Pd, Pt, or combinations thereof.

11. The alloy of claim 1 wherein up to 1.5 atomic percent of Ta is substituted by Nb, V, or combinations thereof.

12. A metallic glass comprising an alloy of claim 1.

13. The metallic glass of claim 12 wherein a ranges from 0.5 to 15, b ranges from 8.5 to 10, c ranges from 2.5 to 3.5, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75;

wherein the critical rod diameter of the alloy is at least 6 mm; and

wherein the notch toughness is at least 55 MPa m^1/2.

14. The metallic glass of claim 12 wherein a ranges from 0.5 to 5, b ranges from 6.5 to 7.5, c ranges from 2.25 to 3.25, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75;

wherein the critical rod diameter of the alloy is at least 6 mm; and

wherein the notch toughness is at least 80 MPa m^1/2.

15. The metallic glass of claim 12 wherein a ranges from 0.5 to 10, b ranges from 8.5 to 10, c ranges from 2.5 to 3.5, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75;

wherein the critical rod diameter of the alloy is at least 6 mm; and

wherein the notch toughness is at least 60 MPa m^1/2.

16. The metallic glass of claim 12 wherein a ranges from 0.5 to 3, b ranges from 6.5 to 7.5, c ranges from 2.25 to 3.25, d ranges from 15.75 to 16.75, e ranges from 2.75 to 3.75;

wherein the critical rod diameter of the alloy is at least 7 mm; and

wherein the notch toughness is at least 90 MPa m^1/2.

17. A method of producing the metallic glass of claim 12 comprising:

melting the alloy into a molten state; and

quenching the melt at a cooling rate sufficiently rapid to prevent crystallization of the alloy.

18. The method of claim 17, further comprising fluxing the melt with a reducing agent prior to quenching.

19. The method of claim 18, wherein the reducing agent is boron oxide.

20. The method of claim 17, wherein the melt prior to quenching is heated to at least 1100°

C.