Nickel titanium alloys, methods of manufacture thereof and article comprising the same

Patent metadata

Field	Value
Publication number	US-2016258043-A1
Application number	US-201414552988-A
Country	US
Kind code	A1
Filing date	Nov 25, 2014
Priority date	Nov 27, 2013
Publication date	Sep 8, 2016
Grant date	—

Abstract

Disclosed herein is a shape memory alloy comprising 48 to 50 atomic percent nickel, 15 to 30 atomic percent hathium, 1 to 5 atomic percent aluminum; with the remainder being titanium. Disclosed herein too is a method of manufacturing a shape memory alloy comprising mixing together to form an alloy nickel, hafnium, aluminum and titanium in amounts of 48 to 50 atomic percent nickel, 15 to 30 atomic percent hafnium, 1 to 5 atomic percent aluminum; with the remainder being titanium; solution treating the alloy at a temperature of 700 to 1300° C. for 50 to 200 hours; and aging the alloy at a temperature of 400 to 800° C. for a time period of 50 to 200 hours to form a shape memory alloy.

First claim

What is claimed is:

1 . A shape memory alloy comprising:
48 to 50 atomic percent nickel, 15 to 30 atomic percent hathium, 1 to 5 atomic percent aluminum; with the remainder being titanium.

2 . The shape memory alloy of claim 1 , where the shape memory alloy has the formula Ni 50 Ti (30−x) Hf 20 Al x , where x can have a value of 1 to 5.

3 . The shape memory alloy of claim 2 , where x has values of 1, 2, 3, 4, or 5.

4 . The shape memory alloy of claim 1 , where the titanium is present in an amount of 25 to 30 atomic percent.

5 . The shape memory alloy of claim 1 , where the alloy displays a compressive strength of 900 to 1200 MPa at a compressive strain of 1.5 to 5%.

6 . The shape memory alloy of claim 1 , where a composition having 3 to 5 wt % aluminum based on the total weight of the alloy, has precipitates of 1 to 10 nanometers.

7 . A method of manufacturing a shape memory alloy comprising:
mixing together to form an alloy nickel, hafnium, aluminum and titanium in amounts of 48 to 50 atomic percent nickel, 15 to 30 atomic percent hafnium, 1 to 5 atomic percent aluminum; with the remainder being titanium; solution treating the alloy at a temperature of 700 to 1300° C. for 50 to 200 hours; and aging the alloy at a temperature of 400 to 800° C. for a time period of 50 to 200 hours to form a shape memory alloy.

8 . The method of claim 5 , where the solution treating is conducted at 950° C. for 100 hours.

9 . The method of claim 5 , where the aging the alloy is conducted at 600° C. for 100 hours.

Assignees

• Univ Florida

Inventors

• Manuel Michele Viola
• Hsu Derek Hsen Dai

Classifications

• C22C27/00

  Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00 · CPC title

• C22C1/00

  Making non-ferrous alloys (by electrothermic methods C22B4/00; by electrolysis C25C1/24, C25C3/36) · CPC title

• C22C30/00 Primary

  Alloys containing less than 50% by weight of each constituent · CPC title

• C22F1/006

  Resulting in heat recoverable alloys with a memory effect · CPC title

• C22F1/18

  High-melting or refractory metals or alloys based thereon · CPC title