High hardness, corrosion resistant PM Nitinol implements and components

• US 9,101,984 B2
• Filed: 11/15/2012
• Issued: 08/11/2015
• Est. Priority Date: 11/16/2011
• Status: Active Grant

• Current Assignee: Carpenter Technology Corporation
• Original Assignee: Summit Materials LLC (Summit Materials, Inc.)
• Inventors: Bono, Eric S., Yolton, Charles Frederick
• Primary Examiner(s): Wyszomierski, George
• Assistant Examiner(s): MAI, NGOCLAN THI
• Application Number:
  US13/677,600
• Publication Number:
  US 20130118312A1
• Time in Patent Office: 999 Days
• Field of Search: 419/28, 419/49
• US Class Current: 1/1
• CPC Class Codes: B22F 1/09 Mixtures of metallic powders
• CPC Class Codes: B22F 2003/247 Removing material: carving, cleaning, grinding, hobbing, honing, lapping, polishing, milling, shaving, skiving, turning the surface
• CPC Class Codes: B22F 2003/248 Thermal after-treatment
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/15 Hot isostatic pressing
• CPC Class Codes: B22F 3/18 by using pressure rollers
• CPC Class Codes: B22F 3/24 After-treatment of workpieces or articles B22F3/1146 takes precedence
• CPC Class Codes: B22F 5/006 of flat products, e.g. sheets B22F3/1103 takes precedence; by using pressure rollers only see B22F3/18
• CPC Class Codes: B26B 9/00 Blades for hand knives
• CPC Class Codes: C22C 1/0433 Nickel- or cobalt-based alloys

Abstract

A manufacturing method for making components includes: providing at least one of a prealloyed powder of a composition of Ni—Ti in the range of Ni-36Ti to Ni-45Ti or a mix of powders that forms a composition of Ni—Ti in the range of Ni-36Ti to Ni-45Ti; loading at least one of the prealloyed powder and the mix powders into a container; hot isostatically pressing (HIP) the container to full density to obtain a compact; rolling the compact in a mill with multiple passes to produce a sheet or other mill form material; and cutting blanks for the components from the sheet material to produce a component blank.

Claims

1. A manufacturing method for making components, comprising:

providing at least one of a prealloyed powder of a composition of Ni—

Ti in the range of Ni-36Ti to Ni-45Ti or a mix of powders that forms a composition of Ni—

Ti in the range of Ni-36Ti to Ni-45Ti;

loading at least one of the prealloyed powder or the mix of powders into a container;

hot isostatically pressing (HIP) the container to full density to obtain a compact;

rolling the compact in a mill above 1200°

F. to avoid cracking with multiple passes to produce a sheet or other mill form material;

cutting blanks for the components from the sheet material to produce a component blank,

heat treating the component blank to achieve a low hardness HRC(27-35) for optimal finishing operations,

conducting finishing metal forming and removal or grinding operations on the component blank in the low hardness condition; and

heat treating a finished component blank to high hardness HRC(45-65) for fine finishing for edge retention and/or durability.

2. The manufacturing method of claim 1, wherein the mix of powders is a mix of nickel and titanium constitutive elemental powders that forms a composition of Ni—

Ti in the range of Ni-36Ti to Ni-45Ti.

3. The manufacturing method of claim 1, wherein the container is manufactured from low carbon steel.

4. The manufacturing method of claim 1, wherein the container has one of a rectangular shape and a round shape.

5. The manufacturing method of claim 1, wherein pressures produced during the hot isostatically pressing (HIP) are between about 10,000 psi and about 30,000 psi.

6. The manufacturing method of claim 1, wherein a temperature during the hot isostatically pressing (HIP) ranges from about 1600°

F. to about 2000°

F.

7. The manufacturing method of claim 1, further comprising encasing the compact in an insulating medium after the hot isostatically pressing (HIP).

8. The manufacturing method of claim 1, further comprising flattening the sheet material to produce flattened sheet material.

9. The manufacturing method of claim 8, wherein the flattening is performed by reheating the sheet material and processing the sheet material in flattening equipment.

10. The manufacturing method of claim 8, further comprising annealing the flattened sheet material.

11. The manufacturing method of claim 1, wherein the cutting is performed by water jet, laser cutting, electronic discharge machining (EDM), or any combination thereof.

12. The manufacturing method of claim 1, further comprising grinding a profile into the component blank.

13. The manufacturing method of claim 12, wherein the grinding is performed using fast speed and relatively shallow pass depths while flushing the component blank with coolant.

14. The manufacturing method of claim 1, wherein the component is a knife.

15. The manufacturing method of claim 1 wherein the prealloyed powder composition contains up to 5% of other alloy elements.