Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Elements 118 and higher = why?

  1. Jul 22, 2004 #1
    let's asume that the higher we go, the more stable the element is, or so i am lead to believe.

    let's asume that at 160, it is perfectly stable. what would be the point? what i mean is, what could we use such a heavy material for? construction? AP ammo? engine blocks?

    it seems to me there are 3 key points to using one material over another.

    1) weight
    2) strength
    3) volume

    eg, you could make a Titanium sword. It would be stronger, and lighter, but it's "volume" would be greatly larger. if it came to engine blocks of a car, this would be bad cos it would make the engine much larger (albeit stronger and lighter)

    so what would such a heavy element be good for?

    which element has the highest strengh to weight ratio?

    caution, the above poster may have no idea what he's talking about.
    Last edited: Jul 22, 2004
  2. jcsd
  3. Jul 22, 2004 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Are you referring to the island of stability? 'Stability' is rather relative; there is an expectation that some nuclides near element 114 will be considerably more stable than heavier and lighter ones, but the expected half-lives are still no more than seconds (or much less). Not much good for car engine blocks :wink:
  4. Jul 22, 2004 #3
    i was talking about that, yes. but what about after that?
  5. Jul 22, 2004 #4


    User Avatar

    Staff: Mentor

    Actually, no - strength of material is generally in terms of volume or area, ie tensile strength is pounds per square inch. Titanium both has a higher tensile strength than steel and a higher strength to weight ratio. So a titanium sword would be both stronger and lighter than a steel one of identical proportions.
    I think its titanium, but you can exceed that with alloys and carbon composites.
    Last edited: Jul 22, 2004
  6. Jul 22, 2004 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    ... the nuclides become increasingly unstable, with half-lives of microseconds or less (OK, maybe one or two get to live as long as a millisecond).
  7. Jul 30, 2004 #6
    A titantium sword might not really be an effective weapon.

    If it were a "thrusting" weapon like a foil or an epee, it might be nice because it would minimize fatigue on the combatant.

    But if titanium were used on a "slashing" weapon such as a sabre, it might not be effective because it doesn't carry as much momentum to it's target.

  8. Jul 31, 2004 #7
    BEC Helium is the strongest material known to man.

    But if you're talking about something more down-to-Earth, then diamond is the strongest.

    Both only contain one element! :wink:
  9. Sep 22, 2004 #8
    How about Lithium in a Vacuum? I am sure it has a large strength to weight ratio, if only because of its low weight.
  10. Oct 4, 2004 #9
    WE also worry about shearing forces. Eg Depleted uranium is agreat for shells because is shows a phenominae called Adiabatic Shearing force.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?