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Science Technology

New Alloy Bounces Back Into Shape 10 Million Times And Counting 65

wrp103 links to the BBC's report of a newly engineered alloy that returns to its original shape after deformation even after 10 million cycles more than 10 million times. From the article: "Memory shape alloys" like this have many potential uses, but present incarnations are prone to wearing out. The new material — made from nickel, titanium and copper — shatters previous records and is so resilient it could be useful in artificial heart valves, aircraft components or a new generation of solid-state refrigerators." (Original article in Science Magazine.)
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New Alloy Bounces Back Into Shape 10 Million Times And Counting

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  • by cduffy ( 652 ) <charles+slashdot@dyfis.net> on Saturday May 30, 2015 @03:05PM (#49805965)

    We can make modern flex nibs better than the old ones!

    (Good flexible fountain pen nibs are pretty much all circa 1950s or prior right now; it's a sad, sad state of affairs).

    • by SeaFox ( 739806 ) on Saturday May 30, 2015 @03:30PM (#49806045)

      Did something change in the late '50s (like material or manufacturing laws) that resulted in poorer quality nibs after that point?

      • by Anonymous Coward on Saturday May 30, 2015 @03:59PM (#49806157)

        When the ballpoint pen came out, Fountain pen makers tried to compete with things like lifetime warranties. Flex nibs, when flexed too far, can spring and not bounce back. When made of expensive metals (14k gold for flex nibs), it made lifetime warranties pretty expensive for the manufacturers to have to replace nibs that people ruin. Saying no to replacing a nib wouldn't go over well, because most people can't admit that they mis-used something. So, to make the warranties stick and to not piss people off, things had to made more durable, i.e. not flexy.

        It got worse when people grew up on ballpoint pens and would buy pens as adults. Ballpoint users are used to pressing hard. Pressing hard can damage nibs. Then we ended up with the ridiculously hard nails of today.

        In addition, some countries (esp. France) regulated the amount of gold has to be in something to call it "gold". Flex pens should be made of 14k, but the French, in their infinite wisdom, made it 18k. That's far too soft for a flex nib, since there isn't enough memory. (And there are even some folks who make 21k nibs, which are just silly)

        Nib metals also need to not corrode too, hence why it's still pretty much stainless steel (which doesn't flex well) or gold (better for corrosion, but18k is too soft). Since there are so few of us who like flexy nibs, it's not worth the research and tooling to figure out new types of nibs. (They've tried titanium, but it's just not that great)

    • Everybody loves a good nib.

    • flexible fountain pen

      I'm left handed you insensitive clod.

      • by cduffy ( 652 )

        Tried Parker Quink, or the Noodler's Bernanke series? Both are quick-drying.

        I'm actually a right-handed overwriter (rare thing that is), so I feel at least some subset of your pain.

    • by Anonymous Coward

      Regular Nitinol (super elastic, not SMA) can do 10 million cycles, no big deal. This is different, it's a shape memory alloy, which means that it's shape is returned by thermal cycling, and Nitinol (shape memory, not SE) can only do a few cycles before becoming permanently deformed.

      Nitinol SE is pretty amazing stuff, I use it in nano positioning fixtures as a flexural bearing after Dan Gelbart showed me the technique. It has as far as I can tell perfect repeatability. The only trouble with Nitinol is it's a

  • Someone isn't considering how incredibly expensive that a copper+titanium refrigerator will be.

  • Anyone remember Roswell, NM?
    • Anyone remember Roswell, NM?

      My first thought exactly. So it took us 60 years or so to figure it out.

      "it was a sheet of metal, very light weight, but you could crush it up like a ball and it would bounce right back no matter what you did, and it would not cut or burn"

      • Well considering that the scanning electron microscope wasn't developed until the late 60's and it took 30 additional years to make a decent one it makes sense.

        I dare you take a modern computer tablet back to 1947 and ask them to make sense of it. I bet they struggle just to keep the battery charged.

        Now you want to figure out anti grav?

        • Oh no, I'm totally willing to cut some slack. This stuff is not easy, be it reverse engineering OR inventing it with original research.

          We're on the edge of unlocking a whole new realm of material science where we can do things that would have looked like magic even 50 years ago. Alien or not, this does show that science can do a lot in a very short period of time.

          • by dbIII ( 701233 )
            Actually the magic here is we can do stuff like this far better than we used to be able to do 50 years ago.
          • by dbIII ( 701233 )
            Here's a bit on the first commercial shape-memory alloy with a fair bit explaining how they are driven by phase transformations - cool stuff.
            http://en.wikipedia.org/wiki/Nickel_titanium
    • by mikael ( 484 )

      "it was a sheet of metal, very light weight, but you could crush it up like a ball and it would bounce right back no matter what you did, and it would not cut or burn"

      I Remember that description. It's always fascinated how UFO reports seem to reflect future technology, even if it was someone tripping out, writing a sci-fi story rather being a real event. Eric von Daniken proposed the idea of quadrocopters, while others propose the idea of 360 panoramic flight decks.

      • by matfud ( 464184 )

        It is far easier to imagine something then it is to make that imagination come to life and actually work.

  • Scientists: Hey guys we've invented this amazing new thing!
    Me: Cool, let's see a video of it in action.
    Scientists: Pfft! We've done one better than that - we've written a paper on it instead.
    Me: Gaahhhhh!!!
    • by SeaFox ( 739806 )

      Yes, a video of a piece of metal bending... and returning to its original shape.
      Bending... and returning to it's original shape.

      Just keep watching... after another 9,999,998 times we think it might do something different.

    • Probably because they don't know what to call it yet.

      Nitinol was just fine, but C*ntinol would probably not go over well.

      No, wait... that would be nitrogen. I bet they're thinking it, though.
  • A step closer to Rearden Metal?
  • Ok lets say it has to be a permanent heart valve.

    For math ease, let's say a heart beats at 60 beats per minute (once per second .. though average resting heart rates are usually a little faster than that).

    So to calculate how many days it will take to go through 10 million cycles we do Number of cycles / (Hours in a day x Minutes in an hour x Beats in a minute) = 10,000,000 / (24 x 60 x 60) = 10,000,000 / 86,400 = 115.74 = about 116 days .. nearly 4 months.

    So unless they can get say 100 million or more

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      They did testing of 10 million cycles and checked for fatigue in the metal - they found only negligible changes, that indicates the metal changes. So while 10 million is what has been tested, the results indicate that it should be able to continue on for a significantly higher number of cycles.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Not necessarily. It's a simple matter to run a series of test to failure at varying stresses to determine fatigue life. Then we can employee Miner's rule to predict fatigue damage for a variety of applications for this new material.

    • by whit3 ( 318913 )

      Ok lets say it has to be a permanent heart valve. So to calculate how many days it will take to go through 10 million cycles ...nearly 4 months. So unless they can get say 100 million or more out of it I don't think this will find much use outside of a temporary heart valve.

      That was ten million THERMAL cycles, where a thermal pulse was used to reset the material to its exact original shape. It can flex thousands of times, weaken, then one thermal cycle can restore it to its original shape (reset it,

  • I've used Flexon frames in the past, but they tend to be heavy. I wonder if this material is lighter.
  • I've always wondered why we don't see any applications using Nitinol.

    The stuff has been around since the 70's. It looks really useful and powerful.

    https://www.youtube.com/watch?... [youtube.com]

    • And the answer is: reliability! From the wikipedia article [wikipedia.org]:

      Fatigue failures of nitinol devices are a constant subject of discussion. Because it is the material of choice for applications requiring enormous flexibility and motion (e.g., peripheral stents and heart valves), it is necessarily exposed to much greater fatigue strains than are other metals. While the strain-controlled fatigue performance of nitinol is superior to all other known metals, fatigue failures have been observed in the most demanding applications. There is a great deal of effort underway trying to better understand and define the durability limits of nitinol.

      I'm betting the reason we haven't heard of these wonderful heat engines mentioned in that 1970's era video is because the nitinol [wikipedia.org] probably tended to break after a few million flexes, which doesn't make for a good, long-term, reliable engine. BTW, we DO actually have many nitinol-based products (see the article). Just not the heat engines.

      It could very well be that this discovery pushes memory shape alloy heat engines into the real

    • Springs in general only bend a tiny bit on any particular part that is why they are so reliable. If you take a spring and bend it at one point say with two needle nose pliers. It will not spring back, but you will have a bent spring.

  • Really wonderful memory metals have been around for at least 25 years now. Industry really wanted the public to not get products containing memory metal all these years. About the only common use of memory metal that the public can find are the wires in womens' bras that return to shape when placed in the hot water of a washing machine. the chances are that we will see very few products containing memory metal as the stuff threatens to many large industries. For example you could have a car that self r
  • Screw the fridges and heart valves.

    Give me pogo sticks and super shoes.

    Make me a set of oscar pistorious legs and some type of new car suspension.

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