Product Description

nitinol memory wire/Nitinol Wire

Nitinol Wire

Nickel titanium, also known as nitinol, is a metal Alloy of nickel and titanium, where the two elements are present in roughly equal atomic percentages.

Nitinol alloys exhibit two closely related and unique properties: shape memory and superelasticity (also called pseudoelasticity). Shape memory refers to the ability of nitinol to undergo deformation at one temperature, then recover its original, undeformed shape upon heating above its "transformation temperature". Superelasticity occurs at a narrow temperature range just above its transformation temperature; in this case, no heating is necessary to cause the undeformed shape to recover, and the material exhibits enormous elasticity, some 10-30 times that of ordinary metal.

Memry’s superelastic nitinol wire supports the most complex of component designs requiring intricate geometric shapes. By fine-tuning the wire’s chemical composition and thermal processing, Memry has achieved wire with the flexibility and kink-resistance central to medical device applications, including stents, catheters, endodontic files, needles, trocars, mandrels, baskets, surgical instruments, snares and guidewires.

Memry can design wire so that it is ready for 100ºC degrees or -100ºC usage or anywhere in between, depending on the application. Clients specify their desired operating temperature, and how the material should behave, and Memry adjusts the composition accordingly. Thus, Memry nitinol wire is useful not just in superelastic applications, but for those that require thermal control, such as switches, actuators.

Brief description

Shape Memory Nitinol wire: TiNi-01 TiNi-02

Super elastic Nitinol wire: TiNi-SS

Medical Nitinol alloy: TiNi-SS

Narrow Hysteresis Nitinol Alloy: TiNiCu alloy

Wide Hysteresis Nitinol Alloy: TiNiNb TiNiFe

Standard: ASTM F2063-05 Q/XB1516 Customer specified or Industry Standard

Size:Bar: Dia6.0mm

Wire:0.05-6.0mm

Sheet:Thickness 0.3-50.0mm Width≤350mm Length≤2500mm

Chemical composition: Ni: 55.4% --56.2% C≤0.07 H≤0.005 O≤0.050 N:≤ 0.05

Physical Properties

Nitinol properties are particular to the precise composition of the alloy and its processing. The presented specifications are typical for commercially available shape memory nitinol alloys.

Melting point: 1310 ºC

Density: 6.45 g/cc

Electrical Resistivity:82x10^-6 Ωcm (Austenite)

76 x10^-6 Ωcm (Martensite)

Thermal Conductivity:0.18 W/cm ºC (Austenite)

0.086 W/cm ºC (Martensite)

Coefficient of Thermal Expansion:11x10^-6/ ºC (Austenite)

6.6 x10^-6/ ºC (Martensite)

Magnetic Permeability:< 1.002

Magnetic Susceptibility: 3.7x10^-6 emu/g (Austenite)

2.4x10^-6 emu/g (Martensite)

Elastic Modulus: 75-83 GPa (Austenite)

28-40 GPa (Martensite)

Yield Strength: 195 - 690 MPa (Austenite)

70 - 140 MPa (Martensite)

Poisson's Ratio:0.33

Applications

There are four commonly used types of applications for nitinol.

Free Recovery: nitinol is deformed at a low temperature, and heated to recover its original shape.
Constrained Recovery: The same, except that recovery is rigidly prevented, and thus a stress is generated.
Work Production: Here the alloy is allowed to recover, but to do so it must act against a force (thus doing work).
Superelasticity: As discussed above, here the nitinol acts as a super spring.

In 1989 a survey was conducted in the United States and Canada that involved seven organizations. The survey focused on predicting the future technology, market, and applications of SMA's. The companies predicted the following uses of nitinol in a decreasing order of importance: (1) Couplings,( 54853881,2) Biomedical and medical,( 54853882,3) Toys, demonstration, novelty items,( 54853883,4) Actuators,( 54853884,5) Heat Engines,( 54853885,6) Sensors,( 54853886,7) Cryogenically activated die and bubble memory sockets, and finally (8) lifting devices.^[17]

Nitinol is also popular in extremely resilient glasses frames. It is also used in some mechanical watch springs.
It can be used as a temperature control system; as it changes shape, it can activate a switch or a variable resistor to control the temperature.
It is used in cell-phone technology as a retractable antenna, or microphone boom, due to its highly flexible and mechanical memory nature.
It is used in some novelty products, such as self-bending spoons which can be used by amateur and stage magicians to demonstrate "psychic" powers or as a practical joke, as the spoon will bend itself when used to stir tea, coffee, or any other warm liquid.
It can also be used as wires which are used to locate and mark breast tumours so that following surgery can be more exact.
Due to the fact it can change shapes it is also used as a golf club insert.
Nickel titanium can be used to make the underwires for underwire bras.