Air Temp Nitinol

[gadgetmall]

I see there is no more sellers selling the good stuff . I have a lot of it and made sure i would never run out of it . I have bought these and they are nice wire . They are already treated though and will return to the u shape everytime ,http://www.ebay.com/itm/5-X-Rectangular-Thermally-Denatl-Activated-Nitinol-Arch-Wires-Best-price-/200714255085?pt=LH_DefaultDomain_0&;hash=item2ebb807aed

I have these also .http://www.ebay.com/itm/DENTAL-ORTHODONTIC-WIRES-THERMAL-NITINOL-RECT-HURRY-/310391441334?pt=LH_DefaultDomain_0&;hash=item4844c587b6

they are very strong but you need ice water . they do get soft . you get 10 per pack on all the medical dental wires .

I have also tried the other ones no marked as thermal and they work you have to anneal them .

get the biggest size 21 x 25  and also the small ones work really well . The one i like the most is 14 x 25 thermal activated upper . They will turn to noodles in cold water and return to oval U shape in warm air and body temperature . i carry one in y pocket and have amazed quite a few people .

I may just have to sell some of my special wire by the foot . I really do not know where to get this ultra pure grade wire cheap . I know Jd medical wants an arm and a leg for three feet of the wire i bought . 85 us for three feet . Plus shipping . Yeaks.  I can do half that easy .My wire can change in just a 25 degree difference and as you read many different temperature ranges well within Normal Ambient air temps thus we don't need to expend any energy other than what God supplies after it is trained .

[johntee]

Hi gadgetmall,

Thanks for your reply. For my device to work at its most efficient I need wire that will be 'noodle sloppy' in cold ground water at around 40 to 55 degrees F and have a fast transition speed to 'rigid' at 70 to 75 degrees F.

On the above information which of the ones you mentioned in your post above would fall into that temperature category?

I notice on on the first link you gave me to:- 

http://www.ebay.com/itm/5-X-Rectangular-Thermally-Denatl-Activated-Nitinol-Arch-Wires-Best-price-/200714255085?pt=LH_DefaultDomain_0&;hash=item2ebb807aed

the Ebay seller just states they are  "THERMALLY ACTIVATED" dental Nitinol wires, there is no mention or indication of transition temperature. If these are suitable which from your experience would be the best sizes to order from those he lists on his Ebay page?

I'm a 66 year old retired pensioner now so I have to spend very carefully these days.

RE: "The one i like the most is 14 x 25 thermal activated upper . They will turn to noodles in cold water and return to oval U shape in warm air and body temperature . i carry one in y pocket and have amazed quite a few people."

I've searched the web for these but cannot specifically locate anything which exactly fits the bill as far as temperature goes. Do you by chance have any lead to the person who is selling these? I do need something which will "turn to noodles in cold water and return to oval U shape in warm air and body temperature"

Sorry, I ask a lot of questions  of you  but I feel you are the most experienced person to guide me on Nitinol use. Many thanks again,

John in the UK.




"People laugh at me because I AM different, I laugh at them because they are all the same"   

[gadgetmall]

Hi. Yes that is the number one problem with finding Nitinol. No one will tell you exactly at what temp it changes . That is because before be there was no published experiments with Ambient Nitinol or there was none until now.

I have the kind that can be trained exactly like that and it is 0.020 diameter . No one is selling it anymore .There is only one place and you have to be rich and that is JDmedical or Nitinol.com . Both of them are more expensive than it's weight in platimium.
As i said the Thermally activated arch wires are the closest thing. I paid 10 cents a pack of 10 long wires . Now they are very much more than that. I have not experimented with them other than take them out of the pack and see that they will get soft in water around 36 37 F  and get strong somewhere near 75-98.6 .. It is cold here in NC but not yet below freezing and still in the 40's 50's .the only wire that changes is the original wire in the 40 foot rolls. It can be trained for  air temps unlike that fake stuff Kelloggs sells. That is not air temp wire . That is not even close to what i have or the thermal arch wire. .
Sorry if i can't help . I can sell a bit of mine but this stuff is very valuable to me . Once you see it work it is one of those things that just needs to be in the safe.

I do sell pieces on craigslist but they  sized about 12 inches for 5 usa postage included . It can be unanealed so an experimenters piece. I cut them up in 2 inch pieces and anneal them for family and friends locally . I also keep several pieces in my pocket in the corner of my wallet . I make small trick wires with latex loops so they don't get lost when you drop them .http://eastnc.craigslist.org/mat/3363835928.html

Gadget

[johntee]

Hi gadgetmall,

Thanks for your speedy reply. If you are willing to sell me some of your wire I'd appreciate that.  I would need 5 foot (60") to evaluate my current project if that is possible. I don't have any capacitors for training the wire, only a variable temperature heat gun to 650 degrees C.


Therefore any exact help using that to train the wire to the cold water / room temperatures I mentioned in my last post would be appreciated

I can pay you by PayPal, although I have never actually paid an individual direct ( Ebay only ) so you'd need to give me details of doing that.

I have just topped up my PayPal account tonight from my bank but the funds will not clear until 21st November so I'd need to wait for that date before I could process the transaction.

I live in the United Kingdom so you need to add postage etc although my last stuff (crap) from Kelloggs came by ordinary letter post.

If everything is OK with you please get back to me with details.

Many thanks again,

John in the UK


"People laugh at me because I AM different, I laugh at them because they are all the same"   

[Tom Booth]

Just some ideas and observations: In general, most of what I've seen as far as uses for Nitinol (power generating uses) involves direct contact with water. My impression is that it does not conduct heat to or from the air as readily or rapidly as it does with a liquid.

So what I've been wondering is if Nitinol used in some power generating application involving heat exchange with AIR might not benefit by having the wire clad with some kind of aluminum or stainless steel fins to assist or speed up heat transfer. This is not uncommon. All sorts of air conditioners, refrigerators, heat pumps etc. use such a method (usually on pipes or tubes, but why not wire?).

I was thinking of something along the lines of these "Wire Wound Fin Tubes" such as illustrated and described on these pages:

http://www.taaming.com/

http://www.indiamart.com/geiindustrial-systems-ltd/products.html

This might increase heat exchange between the air and the Nitinol while remaining flexible.