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Niccolum
Year 2022, Issue 8InfoAuthor: Christine Fordinal Frey
Nickel and memory trainingNickel-titanium alloys remember their shape when they are trainedNitinol Memorymetal Paper Clip - A nickel titanium alloy paper clip has been bent and returns to its original shape when heated.
The effect was first discovered in 1953 during welding work on nickel titanium alloy sheets, the two components that proved particularly useful in further research. These alloys have since been called nitinol.
Shape memory alloys return to their old shape after being bent when the temperature rises. This effect seems to be most pronounced in nickel alloys with titanium or aluminium; the addition of copper seems to intensify the effect, as in NiTiCu (nickel-titanium-copper) or CuAlNi (copper-aluminium-nickel).
The memory must be trained by manufacturing techniques, but then lasts surprisingly long. These alloys hardly fatigue and retain their shape properties for a long time, even against resistances. Shape memory elements can function for several million cycles. Even with small volumes, they do an amazing amount of work to regain their shape when heated.
Shape memory alloys can also remember two shapes - one at high and one at low temperatures. In order for the material to return to its defined shape when it cools, it must also be trained by thermomechanical treatment cycles.
Shape memory alloys can multiply their normal elastic metal reaction by up to 20 times through the memory effect - "superelasticity".Examples from technology:- In space technology, they are used to stretch solar sails.
- In the automotive industry in large quantities for pneumatic valves
- For camera autofocus and optical image stabilization
- The high actuating force is used in hydraulic pumps.
- as medical implants for stents and as a miniaturized blood pump, which is inserted in compressed form into a blood vessel near the heart and unfolds as a pump in contact with the body-warm blood.
- high restoring forces: use in heat pumps
- As actuators, like springs
- Adaptive modification of wings and winglets on aircraft or Formula 1 cars
- Use of Nitinol in endodontics for root canal treatment of strongly curved root canals in which a stainless steel extirpation needle would break.
- as wire in braces
- flexible eyeglass frames
The effect was first discovered in 1953 during welding work on nickel titanium alloy sheets, the two components that proved particularly useful in further research. These alloys have since been called nitinol.
Shape memory alloys return to their old shape after being bent when the temperature rises. This effect seems to be most pronounced in nickel alloys with titanium or aluminium; the addition of copper seems to intensify the effect, as in NiTiCu (nickel-titanium-copper) or CuAlNi (copper-aluminium-nickel).
The memory must be trained by manufacturing techniques, but then lasts surprisingly long. These alloys hardly fatigue and retain their shape properties for a long time, even against resistances. Shape memory elements can function for several million cycles. Even with small volumes, they do an amazing amount of work to regain their shape when heated.
Shape memory alloys can also remember two shapes - one at high and one at low temperatures. In order for the material to return to its defined shape when it cools, it must also be trained by thermomechanical treatment cycles.
Shape memory alloys can multiply their normal elastic metal reaction by up to 20 times through the memory effect - "superelasticity".Examples from technology:- In space technology, they are used to stretch solar sails.
- In the automotive industry in large quantities for pneumatic valves
- For camera autofocus and optical image stabilization
- The high actuating force is used in hydraulic pumps.
- as medical implants for stents and as a miniaturized blood pump, which is inserted in compressed form into a blood vessel near the heart and unfolds as a pump in contact with the body-warm blood.
- high restoring forces: use in heat pumps
- As actuators, like springs
- Adaptive modification of wings and winglets on aircraft or Formula 1 cars
- Use of Nitinol in endodontics for root canal treatment of strongly curved root canals in which a stainless steel extirpation needle would break.
- as wire in braces
- flexible eyeglass frames