Air Temp Nitinol

[Tom Booth]

gadgetmall, I wouldn't sweat it too much. I believe your perceptions are most likely correct and you are not going crazy or anything, it is just hard to believe.

But there are many strange phenomenon in Physics, under certain conditions.

Like at the "triple point", water can freeze and boil at the same time.

The properties of Nitinol are so unusual I wouldn't really put anything past it. Still, I would like to get some and make some of these kinds of observations for myself. My intention is to do just that ASAP.

I went to one website recently that advertised small Nitinol strips of some sort that sounded interesting. there wasn't any price. I emailed for a price quote which I just got back today:

Length                       : 20mm
Quantity                     : 1 pc          Price : $ 1088.00 / pc

Needless to say I'll be looking elsewhere. I noticed you posted some links earlier to some Nitinol wire for sale on Ebay for about $20 or something. I'll check it out.

[gadgetmall]

gadgetmall, I wouldn't sweat it too much. I believe your perceptions are most likely correct and you are not going crazy or anything, it is just hard to believe.

But there are many strange phenomenon in Physics, under certain conditions.

Like at the "triple point", water can freeze and boil at the same time.

The properties of Nitinol are so unusual I wouldn't really put anything past it. Still, I would like to get some and make some of these kinds of observations for myself. My intention is to do just that ASAP.

I went to one website recently that advertised small Nitinol strips of some sort that sounded interesting. there wasn't any price. I emailed for a price quote which I just got back today:

Length                       : 20mm
Quantity                     : 1 pc          Price : $ 1088.00 / pc

Needless to say I'll be looking elsewhere. I noticed you posted some links earlier to some Nitinol wire for sale on Ebay for about $20 or something. I'll check it out.

O yea jdmedical . gave me a quote like that too it was for just a little  strip . and forget www.nitinol.com unless you are really rich .they thinks its gold because they sell to the medical industry that  use it for stents and teeth. I don't think they have caught on that is also comes from china a 500 times cheaper and in the Quality we are getting it off Ebay   16 grams for 19.95 shipping included .the guy who is selling it is also a Nitinol motor maker and sent me some of his Special wire because i bought so much . it is 0.23 . it takes a LOT of cold for that one though .. The guy i posted the link IS the best around in the US and the quality is very high . .
I will keep you posted as progress is made .thanks for the input .


BTW . you can KILL your nitinol with too much heat during annealing and after too . i have several pieces that are dead because i fried them to the point they are just pieces of wire and will hardly move at all .
Albert 

[Tom Booth]

BTW . you can KILL your nitinol with too much heat during annealing and after too . i have several pieces that are dead because i fried them to the point they are just pieces of wire and will hardly move at all .
Albert

About that. Earlier you wrote:

Some tell you 600c or 1122 c . That is BS . As far as i can tell you do not need to get the wire that hot . In Fact you will damage this wires Crystalline properties and mess it up permanently If you get it much higher than 600-700 degrees F. Heres why thru experimenting i have found the perfect ANNEAL for my Nitinol wire . I took three pieces 6 inches long. the first piece i used three high amperage Ultra super caps at 2.7 volts each and used needle nose pliers connected to neg and pos and let the first wire glow red for a bout three seconds then disconnected it very fast and let it fall in a bowl of ice water . The transformation temp is high as it takes very hot water to transform . The second piece i used two ultra caps 5.4 volts and did the same thing except i let it barley glow then dunked it in ice water . the transformation now occurs at luke warm water ..Now the third piece i used only one 2.7 volt ultra cap .. I watched the wire change color from golden amber to blue,no glow then dunked it in ice water . Now i have air temp Nitinol and will change to the  austenite stage at room temperature and really fast using body temp and it only needs cool water not ice water to make it flexible and in the martensite state . So DO NOT LET THE WIRE GET RED .you only need enough heat to change the wires color then ice water to anneal it to make air temp nitinol.

This is probably an ignorant question but I'm not really familiar with capacitors, except that we used to have fun shocking each other with them in small engine repair class back in high school.

Is there a difference between "ultra caps" and "ultra super caps" ?

Where can I get these - Radio Shack ? I live in the country and there isn't much else around here in terms of electronics. An old computer maybe ? I ave a few of those around.

Any particular brand of ultra cap ?

Why a capacitor and not just a regular battery ?

Also, do you have to wait until it is hot before bending it or could you, for example, if you wanted to make a spring,... wrap it around a ceramic cylinder and clamp it in position and then put the whole thing in a really hot oven (Self cleaning cycle ?).

Is dropping it in ice water absolutely necessary or could you just let it cool down gradually ?

I never worked with this stuff before so I hop you don't mind all the questions. Also I don't want to spend money on the stuff and then just end up ruining it out of sheer ignorance so any additional details, tips or whatever about this annealing process would be welcome.

One other thing. Now if I can remember what it was I wanted to ask.

Oh yeah, the instructions you gave were for a 6 inch piece of Nitinol. What thickness ? What if the piece I want to anneal is shorter, longer, thicker,  thinner...

Probably just have to experiment I guess. I don't suppose you've worked up a specifications chart for annealing different lengths or anything but I guess it doesn't hurt to ask.

Anything else I would need to know in regard to working with this stuff ?

You mentioned you were on the East Coast and it was 116 degrees at the beginning of the thread. I'm also on the East coast (USA) but further north no doubt as it was hot here (New York) this summer but not THAT hot .

[gadgetmall]

Hey Tom :see this demo http://www.youtube.com/watch?v=EoWMF3VkI6U
  The Ultra Caps are like batteries . they have massive amperage in a small package . here are the Specs and Brand:
Maxwell ultracapacitors Bcap1200
Capacitance: 1200.0 F -10/+20%
Voltage: 2.7V
Dimensions: L = 74mm, OD = 60.7mm
Temperature Range: -40°C to +65°C

Features:
2.7V operating voltage
Ultra low internal resistance
Over 1 million duty cycles
Threaded terminal

Applications:
Backup power
Grid Stabilization
Transportation
Automotive subsystems
Rail system power

They have them on ebay much higher farads 2700 farads  2.5volts /  will fry penneys in a flash
http://www.ebay.com/itm/Maxwell-2600-Farad-2-5V-Ultracapacitor-solar-power-storage-EV-used-/300634728406?pt=US_UPS_Batteries_Components&;hash=item45ff39e7d6

i use them instead of batteries because they have so much power and last longer than batteries and i can series them to match the wire length Plus they last for months charged up and it takes me 1 Minuit to charge a string of 7 ultra-caps with my 30 amp smart charger. the Nitinol has a high resistance and the longer the more power you need . . i have over 50
of them . ranging from 650 farads to 2700farads all 2.5- 2.7 volts each . i can control the heat with these . i cannot with a battery or a battery does not have enuff amperage to heat the wire to a proper anneal.these  6 of the 650 farads will start my truck or run my inverter . i have some on solar panels and some on projects . they are worth the money as they never wear out over one million charge discharge cycles more than my life time and they are light .

The Length of that roll is 40 feet long . the thickmess is supposed to be .020 about the size of a second string on an electric guitar or the size of a straight pin. it will stick you with a one inch piece .

the pieces i carry on me i put loops on the ends and covered them in latex so i dont get stuck anymore .

you can cut it with a strong pair of cutters but you cannot fatten it up .

The process of anneling is also the process of training the wire to transform from how to cold so yes the hot is quenched with ice cold water . to make a spring i use a ceramic rod and clamp one end wind it [very  very hard to do) and kkep the tention on it with a pair of needle nose pliers and either hit it with a tiny torch on the table running or hot it with super cap set up made to touch the pliers with clips . once it smokes i have a big bowl of crushed ice and water and dunk it my hands and pliers in it then do it over again at least 3-5 times / if you do that you train it to learn warm from cool and change in tap water and inside air .

[Paul-R]

The Ultra Caps are like batteries .

As they are discharged, does the voltage start dropping immediately, or like
a battery, do you get most of the power at the rated voltage, which drops
as the cap empties?