Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Science

Material Tougher Than Diamond Developed 237

Posted by Zonk from the diamond-is-so-20th-century dept.
sporkme has handed us a link to a New Scientist article. The piece outlines the development of a new substance reported to be stiffer than diamond. A team of scientists from Washington, Wisconsin, and Germany combined the ceramic barium titanate and white-hot molten tin with an ultrasonic probe. The new material was, in some tests, almost 10x more resistant to bending than diamond. Composite materials researcher Mark Spearing of Southampton University comments on the result: "The material's stiffness results from the properties of the barium titanate pieces, Spearing says. As the material cools, its crystal structure changes, causing its volume to expand. 'Because they are held inside the tin matrix, strain builds up inside the barium titanate,' Spearing explains, 'at a particular temperature that energy is released to oppose a bending force.'"
This discussion has been archived. No new comments can be posted.

Material Tougher Than Diamond Developed More

Material Tougher Than Diamond Developed

Comments Filter:

  • Wait a minute (Score:3, Funny)

    by BenjiTheGreat98 ( 707903 ) on Saturday February 03, 2007 @11:39PM (#17878460)
    Stronger than adamantium?!?!?

    • Re: (Score:3, Insightful)

      by CastrTroy ( 595695 )
      Maybe this is the fabled adamantium we have been waiting for. What I want to know, is how likely is it that this stuff can be produced with any kind of industrial volume in the next 10 years.

      • Re:Wait a minute (Score:5, Informative)

        by the eric conspiracy ( 20178 ) on Sunday February 04, 2007 @12:01AM (#17878586)
        Actually the word diamond is derived from the Greek word adamas, so in fact diamond is adamantium.

        • Re: (Score:2)

          by mblase ( 200735 )
          so in fact diamond is adamantium.

          Diamond is a metal?

          • Re: (Score:3, Funny)

            by Nicholas Evans ( 731773 )
            It's the hardest metal known to man. Duh.

            (Note to mods: Yes, this is an old joke. [wikia.com])

            • Re: (Score:2, Funny)

              by Ltar ( 1010889 )
              if they could make a car out of this.... and run it into a wall of it... what would happen?

              • Re:Wait a minute (Score:5, Informative)

                by peragrin ( 659227 ) on Sunday February 04, 2007 @09:38AM (#17880682)
                the driver would die.

                Your car isn't made of steel any more but foldable, collapsable sections so the car takes damage instead of the people inside. Literally the materials are designed to bend at certain deceleration speeds. This goes back to the passenger compartment, where those sections suddenly become stronger. Ever notice how in a car wreck the only thing in one piece is the passenger compartment? The entire engine will go missing first.

                • Re:Wait a minute (Score:4, Informative)

                  by v1 ( 525388 ) on Sunday February 04, 2007 @03:14PM (#17882442) Homepage Journal
                  Another good thing to look up is "crumple zones", the areas of a vehicle designed to collapse while absorbing energy. In most cars, a head-on collision is supposed to force the engine and transmission down and out the bottom (since they are too solid to crumple) and the rest of the engine compartment collapses in on itself and hopefully slows down the vehicle or the intruding object to a safer speed before the crumple zone has been totally crushed and the remaining force starts in on the passenger area.

                  The trunk has less to worry about, there is no massive steel (engine or transmission) to get rid of so it is just designed to crumple and absorb energy of impact.

                  What amazes me is how well cars survive getting T-boned. In many cases the front end of the offending car is usually totally demolished and yet the struck driver's door is only pushed in a few inches.

                  The tradeoff of all this is the vehicle's odds of surviving. If you are in a 52 packard you can run into a wall at 20mph and not do a whole lot besides ruin the bumper. They'll be pulling your head out of the windshield however. Try that with a Taurus and all you'll notice is the airbag, until you go looking for the front of your car and find it in the trunk. Cars used to be designed to survive accidents. Now they are designed to protect their passengers instead. People cry about how expensive it will be to fix a modern car after running into a tree, but they shut up real fast when you point out they would be in a body cast right now if it weren't for all that damage to their car.
              • I imagine it would be like a feather landing on a pillow, for very large values of feather, and pillow.

        • Re:Wait a minute (Score:4, Informative)

          by dsanfte ( 443781 ) on Sunday February 04, 2007 @12:37AM (#17878780) Journal
          adamas, adamantis  N  M     3 6  M   [XTXCO]
          steel, hardest iron (early); anything hard, adamant; white sapphire; diamond;
      • And how, pray tell, would you machine it?
        Anything cast at high temperature will need to be machined to have a precision fit (cylinder sleeves, piston heads, valves, etc.). If nitride or diamond tools are softer then they won't, well, cut it.
        -nB

        • Re:Wait a minute (Score:5, Informative)

          by mollymoo ( 202721 ) on Sunday February 04, 2007 @01:32AM (#17879070) Journal
          TFA says it's stiffer than diamond, that doesn't mean that it's harder than diamond.
          • The slashdot headline actually says "tougher" - which isn't the same either.

          • And even that... (Score:5, Informative)

            by IdahoEv ( 195056 ) on Sunday February 04, 2007 @01:03PM (#17881668) Homepage
            ... doesn't mean it's tougher than diamond. Any mechanical engineer will remind you that strength, stiffness, and toughness are three different properties. IIRC my materials engineering class 15 years ago, they are approximately:

            strength: maximum load before failure

            stiffness: resistance to deformation

            toughness: tendency to avoid reduction in strength over time in the face of repeated deformation

            also:

            hardness: ability to resist permanent deformation, particularly vs. small surface insults like scratches and indentations.

            Diamond is very strong, very stiff, and very hard but it is definitely not tough: large blocks of the stuff are fairly brittle and tend to crack and chip. In fact extremely stiff materials are often not tough because they are brittle. OP has a very screwed-up title.

            From TFA, we have no idea whether or not this new material is either strong or tough or hard: only that it is extremely stiff. (cue tasteless jokes)

            • Re: (Score:3, Informative)

              by florescent_beige ( 608235 )
              Toughness has both a qualitive and quantitive meaning. As someone mentioned before, it can be thought of as the amount of energy (the area under the stress-strain curve) required to fail the material. As a general rule, materials in the same class show an inverse relationship between strength and toughness.

              It also has a quantitative definition that relates to crack sensitivity. Fracture toughness has a specific definition that relates to the strength of the stress singularity at a crack tip required to ma

        • Re:Wait a minute (Score:5, Informative)

          by iq in binary ( 305246 ) <iq_in_binary@hRASPotmail.com minus berry> on Sunday February 04, 2007 @06:46AM (#17880104) Homepage
          Just because it's stiffer doesn't mean that it's harder. (god there are so many things wrong with that statement on so many levels)

          Note however that we don't need a stonger abrasive material. Grinding works on the basis of extreme velocity on the part of the particles in the abrasive wheel or band to do the cutting work. Aluminum oxide would work for the purposes of grinding this material into print. Given that it's a ceramic within a tin matrix; ALO2 would do beautifully.

          As for heavy cutting work, Tungsten Carbide would do just as well. I don't see anything to indicate that the material is HARDER than carbide.

          And speak of the applications..........to tell you the truth there really aren't that many widespread uses for a material like this. For now, with the expense of this material that's going to stay as it is for quite a while, there are FEW cases that would warrant using this material.
      • Is it as hard (obviously not as large) as Lois's excited Superman prick? Yep, that's right Sup is a pussy-whipped man in tights.
  • "Faster than a speeding bullet, more powerful than a locomotive, and able to leap tall buildings in a single bound!" What are they going name this new SuperMaterial??
    Sorry, I couldn't resist

  • That's impossible! (Score:4, Funny)

    by Bobdoer ( 727516 ) on Saturday February 03, 2007 @11:42PM (#17878486) Homepage Journal
    Diamond is the hardest metal known the man!

    • Re: (Score:3, Informative)

      by CastrTroy ( 595695 )
      Actually, according to wikipedia [wikipedia.org] it isn't. It's the hardest natural material (which I think is what you meant, not metal). There are actually 2 known matericals that are stronger, and probably a third material after the one in this article is added to the article.

      • Re:That's impossible! (Score:5, Funny)

        by Anonymous Coward on Saturday February 03, 2007 @11:53PM (#17878538)
        Whoosh?
      • There are more information about hard materials, relationship of stiffness and hardness at this wikipedia article [wikipedia.org].

      • Re:That's impossible! (Score:5, Informative)

        by Falladir ( 1026636 ) <kingfalladir@yahoo.com> on Sunday February 04, 2007 @01:04AM (#17878924)
        Don't conflate hardness with strength or stiffness. Hardness is not well quantified. For hardness we refer to the Mohs scale [wikipedia.org], which will tell you which of two substances is the harder, but doesn't strictly quantify hardness. A claim that substance A is "twice" as hard as substance B probably refers to the Young's Modulus [wikipedia.org], or stiffness, rather than to hardness.

        A common way to measure the Young's modulus is to support a sample of the material on two struts, and then apply pressure from above to the center of the sample. The less it bends, the higher the Young's modulus. The apparatus looks like this [doitpoms.ac.uk].

        Strength is a different quantity. Strength is the amount of force needed, per unit cross-sectional area, to cause the material to fail. For tensile strength, this means pulling apart. For compressive strength, it means collapsing. A material with great tensile strength can have a great weight hung from it without snapping, and a material with great compressive strength can act as a pillar to support a great deal of weight.

        The article claims nothing about the strength of this material.
        • This is making me hard.

          And, by my nickname, I *am* a metal. :P
        • Hardness is the resistance to indentation (or scratching).

          The summary also confuses toughness (resistance to impacts) which is usually mutually exclusive with hardness. Hard substances like diamond aren't tough. The hardest steels are brittle and not at all tough. You can smash them with a hammer like it was glass.

        • Toughness... (Score:3, Informative)

          by TerranFury ( 726743 )

          True... and "toughness" is not the same as "stiffness" either. "Toughness" refers to a material's resistance to failure by fatigue (whereas "stiffness" is, as you said, resistance to bending -- Young's Modulus). They are clearly not the same thing, as there are plenty of brittle materials which are stiff yet fail quickly in fatigue.

          On a related subject, do you ever wince when somebody on TV refers to something that can push harder as being more "powerful?" Or who talks about some kind of battery having

        • Parent is completely right. Once again stupid headline writers fuck up.

          Hardness, toughness, stiffness are all different. Gimme a $2 claw hammer and your wife etc's $2000 diamond ring and I'll soon show you which is tougher.

  • Space flight (Score:5, Interesting)

    by Ekhymosis ( 949557 ) on Saturday February 03, 2007 @11:44PM (#17878496) Homepage
    Will this material be light enough for future space exploration, such as space stations and colony materials? Or is the cost associated with making it too prohibitive? How about the melting temperature/pressure resistance for deep earth exploration?

    • Re: (Score:3, Interesting)

      by Myrcutio ( 1006333 )
      one application i can think of for space travel is to use it in the hull of a ship to deflect particles traveling at high speeds. You could use an electrical current to heat this material to 58 degrees celsius in a short amount of time, all you would need is a method of detection that could locate the particles a few seconds before impact, and you've got a barrier 10x harder than diamond in between you and vacuum. As far as costs go, i think NASA can afford it, isn't all the wiring on the shuttle solid go

    • Not really. Here's how it works (sort of) (Score:5, Informative)

      by Richard Kirk ( 535523 ) on Sunday February 04, 2007 @07:44AM (#17880284)

      Barium titanate is a structure called a spinel. It has oxygen ions packed in a face-centred cubic structure, with the barium and Titanium ions stuck on the holes between. Above a certain temperature, spinels are cubic. however, at lower temperatures, the structure can reduce its energy by breaking symmetry and squashing a bit down one of the cubic axes, becoming orthorhombic. This compression is not huge, but it is a lot bigger than the typical stretchings you get due to thermal expansion or mechanical stress.

      Stick the spinel structure into a tin matrix and cool it. If you are ingenious about your choice of tin matrix, then the stress on the tin can actually get the spinel to change its shape in a way that opposes the bending, rather than going with it as you might expect. Tin is funny stuff - it also has a change in crystal structure on cooling from cubic to hexagonal (though at a much lower temperature) so I guess it is somehow squeezing the spinel in some anisotropic fashion and triggering the phase change.

      This is ingenious stuff but it isn't really a high stiffness in the normal sense, any more then the compound pendulums you can somtimes find in grandfather clocks have a very low thermal expansion coefficient. Those have brass and steel rods which all have expansion coefficients, but they are put together in a way that makes the stotal expansion zero. Supposing you had a piezo crystal, with attached electronics that applied a voltage causing it to resist any force put upon it. You could make this infinitely stiff depending on your level of control, or even have it push pack on what is pressing on it.

      So, back to your original question. It is heavy, and it only demonstrates the stiffness over a limited range. Bulk material stiffness is not usually important - you can make stiff structures like a cage of tubes by design. However, if you wanted to make some structure appear perfectly stiff, then some active control like the hypothetical piezo stuff I described earlier would probably be lighter and better. I would love to know what this ingenious stuff is for, but I don't think it is for space.

  • "Stiffer" than diamond???

  • Ah misleading Slashdot article titles... (Score:5, Informative)

    by tylersoze ( 789256 ) on Saturday February 03, 2007 @11:46PM (#17878510)
    I love them almost as much as dupes. :) Material Tougher Than Diamond Developed...(in some tests), like say: "The tests were carried out at a variety of temperatures. Between 58C and 59C the samples became stiffer than diamond."

    Not to knock the experiment though, it seems interesting, and I'm sure there are all sorts of new exotic materials on the horizon.

    • Re: (Score:3, Interesting)

      by topical_surfactant ( 906185 )
      ...and within that narrow temperature window, only some samples proved to be significantly stiffer than diamond. I agree - article title gets an F, but experiment maintains interesting factor.
      • I'm not so sure this is a particularly interesting experiment - the stiffness arises from the internal stresses in a two phase matrix rather than an intrinsic property of the material. As such this is going to have a relative small number of applications.

        • This specific material may have no practical applications at all. The knowledge gained from developing and studying it, however, may lead to many useful applications.

    • Not to knock the experiment though, it seems interesting, and I'm sure there are all sorts of new exotic materials on the horizon.

      It is certainly an interesting development - actively using the residual strains in the material to enance the stiffness. If the temperature window was wider, and closer to usable temperatures, it might be useful.

      I'd like to see the relationship between the apparent Young's modulus and temperature, at least for -40C to +40C. Seeing that the matrix is tin, I'm guessing that h

  • Bah (Score:5, Informative)

    by MadUndergrad ( 950779 ) on Saturday February 03, 2007 @11:49PM (#17878526)
    Toughness != Stiffness

    http://en.wikipedia.org/wiki/Toughness [wikipedia.org] : Toughness

    http://en.wikipedia.org/wiki/Stiffness [wikipedia.org] : Stiffness

    • Re: (Score:2)

      by be-fan ( 61476 )
      The funny thing is that, like most materials which are very stiff, diamond isn't very tough at all.

    • Re:Bah (Score:4, Informative)

      by Andy Dodd ( 701 ) <atd7NO@SPAMcornell.edu> on Sunday February 04, 2007 @01:19AM (#17878998) Homepage
      And also, hardness != either of the above, and *hardness* is the material property diamonds are known for (in addition to having a reasonably high index of refraction, although not the highest by any means.)

      The most typical test of hardness is attempting to scratch a material. (To measure a material's hardness on the Mohs scale, essentially a series of scratch tests are performed, and a material's place on the Mohs scale was determined by what it could scratch vs. what would scratch it.)

      I don't know about stiffness, but diamonds are definately not *tough*. As your links above show, "toughness" is resistance to fracturing under stress, and one of the ways diamonds are cut and shaped is by fracturing them along their crystal lattice planes. There are plenty of materials (Including, I believe, many plastics) that are *tougher* than diamond, but not necessarily harder. (For example, I believe ABS plastic and polycarbonate plastic are extremely tough, but neither are hard - i.e. they are VERY difficult to break via stress and impact, but scratch easily.)

      • Re: (Score:2)

        by bmo ( 77928 )
        "The most typical test of hardness is attempting to scratch a material. (To measure a material's hardness on the Mohs scale, essentially a series of scratch tests are performed, and a material's place on the Mohs scale was determined by what it could scratch vs. what would scratch it.)"

        In the machining world and other places, where more accuracy is needed, "hardness" is defined as "resistance to penetration" or "resistance to plastic deformation, usually by indentation" (Metals Handbook) as in a diamond or

      • I don't know about stiffness, but diamonds are definately not *tough*.

        Diamond is very stiff. It has a Young's modulus of about 1000 GPa. Compare this to steel at about 200 GPa, titanium at about 100 GPa or aluminum at about 70 GPa. Silicon carbide is about 450 GPa.

        But yes, the toughness isn't good - the cleavage planes are easy to split.

  • Stiffer than diamond? (Score:4, Funny)

    by Anonymous Coward on Saturday February 03, 2007 @11:52PM (#17878532)
    I can't wait to get that spam...
  • Diamond is the best conductor of heat known. Given it's crystlian structure I wonder what it's thermal properites are or even it's electrical conductivity? Even if it's expensive it could be useful in applications like computer chips.

  • Hardness != toughness, get it right (Score:5, Informative)

    by Dr. Zowie ( 109983 ) <slashdot@defores t . org> on Sunday February 04, 2007 @12:07AM (#17878630)
    Toughness is a measure of the amount of energy necessary to break a material. Hardness is a measure of the amount of pressure required to deform it. The two are not the same. In fact, diamond is not a particularly tough material -- which is one reason why folks are discouraged from wearing diamond jewelry when, say, rock climbing. It's easy to fracture a diamond by bashing it against something even moderately hard -- even though no mineral is harder than the diamond, good ol' granite is much tougher.

    • Re: (Score:2, Informative)

      by Tomfrh ( 719891 )
      even though no mineral is harder than the diamond, good ol' granite is much tougher

      Toughness (units in MPa m^0.5)

      Granite: ~2
      Diamond: ~3.5
      Steel: ~100

      Toughness is a combination of strength and ductility. Granite is medium strength and very low ductility. Diamond is high strength and very low ductility. Steel is medium strength and high ductility.

    • Re: (Score:2, Funny)

      by RealGrouchy ( 943109 )
      Good ol' rock. Nothing beats that! /simpsons

      - RG>
    • I think there are different kinds of hardness. One is a kind on pressure resistance as you say, there is another scale used to rate scratch resistance.
    • Diamond, whether natural or synthetic, is not the hardest known material. Aggregated diamond nanorods are 1.11 times harder than diamond, as discussed here in 2005 [slashdot.org]. And Acetylene polyyne [jpost.com] is 40 times harder than diamond. See here [wikipedia.org]

  • Nope (Score:5, Funny)

    by Anonymous Coward on Sunday February 04, 2007 @12:23AM (#17878708)
    Try again. Chuck Norris is the toughest material on earth, and he just snapped it in two using a karate chop.

    • Re: (Score:3, Funny)

      by TempeTerra ( 83076 )
      True, but Chuck Norris was forged in an immense burst of energy at the very creation of the universe. This material can be produced in a lab, unlike Chuck Norris.

  • resistant to bending .... (Score:5, Interesting)

    by Ace905 ( 163071 ) on Sunday February 04, 2007 @12:38AM (#17878796) Homepage
    There's so many ways to measure the qualities of a material, I don't think anybody would be surprised to know steel is more than 7 times denser than water. But some people would be amazed to find Mercury is almost twice as dense as steel.

    This, "resistant to bending" terminology seems like a real stretch of imagination to me. When do we, as average people ever consider the force involved in -bending- a diamond? It really doesn't sound like a practical thought experiment, and therefore doesn't sound even mildly interesting.

    Spider's Silk is 'stronger' than steel - we've all heard. But there's about 1000 reasons you can't build a ship, or a building or even a walking-cane out of spider's silk.

    This just sounds like bad hype to me ; what I want to know, and what I think everybody wants to know is - will you be able to CUT THE DIAMOND with this material. Diamonds have been the upper-limit of our prowess with cutting-wheels ; do you have a better material for grinding and cutting? Don't confuse the issue.

    Unfortunately I couldn't read the article (slashdotted? what the hell) so I'm going based on the write-up available. don't hate me if the article answers my question.

    ---
    hate me? nahhh [douginadress.com]

    • Re:resistant to bending .... (Score:5, Interesting)

      by Falladir ( 1026636 ) <kingfalladir@yahoo.com> on Sunday February 04, 2007 @01:28AM (#17879044)
      will you be able to CUT THE DIAMOND with this material

      No, you will not. The material is only stiffer than diamond in a narrow temperature range. If you tried to cut with it, it would heat up and lose this stiffness.

      The article does a lousy job of explaining this temperature-dependent stiffness to non-experts. From what I understand, this is how it works: one of the two components is like a framework of tinkertoys, and the other is like a bunch of water balloons filling up the gaps in the tinkertoy structure. Both the tinkertoys and the water expand as the material's temperature is increased, possibly at varying rates. In that small range at 58 degrees F, the water baloons fit very tightly in the structure. They strain the tinkertoys, but don't break them. The tinkertoys flex as they usually would because the water balloons are holding them in place, so the entire assembly is very stiff.

    • Re: (Score:3, Informative)

      by TubeSteak ( 669689 )
      Here's the most relevant portion of TFA:

      Once ingots of the new composite had cooled, rectangular or cylindrical samples 3 centimetres long and 2 millimetres across were tested for stiffness. The response of the samples to bending was tested by gluing one end to a strong support rod and the other to a magnet with a small mirror attached.

      Rhythmic force
      An electromagnet was used to exert a rhythmic force on the material one hundred times per second. The resistance of the composite to the bending force - called

    • Re:resistant to bending .... (Score:5, Interesting)

      by jd ( 1658 ) <imipak@ y a hoo.com> on Sunday February 04, 2007 @02:00AM (#17879170) Homepage Journal
      Diamond (hardness of 10) is the hardest naturally-occuring mineral, but it is not the hardest material. Ultrahard fullerite is close to twice as hard as diamond. Boron-carbide, tungsten-carbide and silicon-carbide (hardness of 9 each) are only marginally softer. Osmium (as well as being the most expensive metal and the densest metal) is as close to diamond as pure metals get (hardness 7), but doesn't quite cut it. (Pun intended.)

      The hardest known material, at present, would be aggregated diamond nanorods. (These are apparently produced by crushing buckyballs at extreme pressures. What "Get Fuzzy" makes of this is currently unknown.)

      • Ultrahard fullerite is close to twice as hard

        I think you've been reading too much herbal v1agra spam.
      • i work with precious metals (or transition metals to chemists), and osmium is nowhere near the most expensive metal. Rhodium is, BY FAR, the most expensive metal. it makes a great catalyst for many things, but due to cost is not a practical lab catalyst.
        Next is rhenium, then platinum, then come all the rest. Osmium might even be lower than gold, although I am not sure.

        • Re: (Score:2)

          by jd ( 1658 )
          Last I looked, Osmium is around 4.5 times that of gold.
          • prices per ounce:
            osmium: $400
            gold: $630
            rhenium: $2000
            rhodium: $4000

            maybe they found a new source of osmium since you last checked.

            • Re: (Score:2)

              by jd ( 1658 )
              Just double-checked and your prices are indeed correct. Since I could find no reference to a new source or a new extraction technique, I resorted to checking the wiki page [wikipedia.org] for Osmium. I'm guessing I must have been looking at the price for Osmium-187, which is indeed about four times the price of gold, as that would explain why we were getting hugely different values. My apologies for not checking more carefully WHICH Osmium I was looking up the price for.
  • Isn't there a carbon nanotube type molecule that's tougher than diamond? I've read about it but I forget the name of it.

      Then again it's all just carbon anyway.

      Ah ha! Found it... http://www.newscientist.com/article.ns?id=dn7926 [newscientist.com]

    • Re: (Score:3, Informative)

      by jd ( 1658 )
      The Wikipedia article on aggregated diamond nanorods [wikipedia.org] is a little more helpful. However, there is a non-carbon material harder than diamond (ultrahard fullerine). What we seem to be seeing is that exotic materials form at the real extremes of pressure and/or temperature - that remain stable at normal atmospheric pressures and temperatures. We also know that crystals form very differently under extreme changes in pressure and/or temperature. This discovery isn't particularly earth-shattering in and of itself.
      • >However, there is a non-carbon material harder than diamond (ultrahard fullerine)

        Did you mean "non-diamond"? It's still a carbon based material, C60 polymerized.

        Carbon. Is there anything it can't do?
  • "I suppooooose it could be a bit of pre-animate matter caught in a matrix..."
  • Tin Barium Titanate is forever? (at a very specific temperature)

    Is it also a girl's best friend?
  • Article title says material is "tougher" than diamond. Article actually says material is "stiffer" than diamond. That's a completely different material property. Can we please get stuff like that right?
  • Finally! A material that can challenge ... Iron Man!

    Or not. :)
  • It's not that easy but it should be looked up before putting an incorrect headline up - stiffness, toughness and strength are different things.

    Stiffness is how much something flexes when you apply force (or pressure which is force per unit area). If it can bend back again this gets called the modulus of elasticity. If you plot pressure against the amount the thing changes shape you get a line for a lot of materials to start with - and the slope of this line is the modulus of elasticity - if you let it go

  • Comment removed based on user account deletion
  • That doesnt mean its stronger..
  • Trying to get sex after giving your girl a 'ceramic barium titanate and white-hot molten tin' engagement ring.

  • I needed an Allen Key in a small size that I didn't have.

    I took a nail and filed one end to make a hexagon of the correct size.

    I bent it to the traditional L shape. Nails are "tough as nails" so it bent without breaking.

    I attempted to undo the socket cap screw. The edges of my hexagon got squished. Nails are "hard as nails"? Wood thinks so, but socket cap screws are unimpressed.

    Plan B: file a hexagon on the end of a piece of "silver" steel. Heat to cherry red on gas stove. Quench. Bake at gas mark 9

    • Nails arent tough, they're usually mild steel. The very fact that they can bend with out breaking indicates that it's quite ductile.

      By adding extra alloying agents (usually more carbon), you get a stifer material, but it will fracture instead of bending.
  • ...diamonds are forever. This thing has how much time to catch up on?
  • So all your need is some titanate to get stiffer?

    Didn't we already know that?

Slashdot Top Deals

A morsel of genuine history is a thing so rare as to be always valuable. -- Thomas Jefferson

Close