Date: Sun, 2 Oct 2005 11:45:24 -0400 (EDT)

Author: Steve Wonnell

Subject: Re: Atomic Trampoline, was: Concave Glass for Bouncing Ball Bearing

Post:


Andy, it's no secret, it's Vitreloy (ZrTiCuNiBe),
a far-from-family variant of the nickel-zirconium-titanium
family that's famous for unusually (meta-) stable amorphous
metal compounds.

-- Steve W.


On Fri, 30 Sep 2005, A Gavrin wrote:

> Date: Fri, 30 Sep 2005 15:53:55 -0500
> From: A Gavrin
> Reply-To: tap-l@listproc.appstate.edu
> To: tap-l@appstate.edu
> Subject: Re: Atomic Trampoline, was: Concave Glass for Bouncing Ball Bearing
>
> The metal is a very complex alloy. i am not sure if the exact
> composition has been published, or if it is a trade secret. They, though
> is that it is amorphous (glassy): it has no crystal structure. How it is
> made is a wonderful story.
>
> The usual method for getting an amorphous material is to quench rapidly
> from a melt. The fast you can quench, the more likely to get a glass,
> but the minimum quenching rate depends on what atoms you throw in there.
> The best situations are ones in which the ionic radii of the components
> are very different. The material in question was developed in the early
> 90's by William Johnson of Caltech (Dept. of Materials Sci.) He worked
> for years to find an alloy system (with at least 5 components) with just
> the right range of atomic sizes (and some other properties) to get an
> alloy that could be "slow quenched." So slow, that casting in a mold and
> air cooling counts as a "quench!" As I recall, the first paper he gave
> on this subject involved an alloy of Zr, Be, Si, and a few others I
> forget. The Be was a tough point. highly toxic!
>
> - Andy
>
>
>
> Clarence Bennett wrote:
>
> >> Cliff, that ball bearing
> >> bounces *almost* indefinitely on the amorphous slab.
> >
> >
> >
> > What is that marvelous metal, and how is it processed?
> >
> >
> >
> >
> >> It bounces several orders of magnitide longer than
> >> a ball bearing bouncing on steel, and maybe one
> >> order longer than bouncing on glass.
> >>
> >> Steve W.
> >
> >
>
> --
> Andrew D. Gavrin
> Associate Professor of Physics Associate Dean, IUPUI School of Science
> LD 222, 402 N. Blackford St.
> Indianapolis, IN 46202-3273
>
> 317-274-6909 (Phys)
> 317-274-0636 (Sci)
> agavrin@iupui.edu
>
>


************************************************************************
Steven K. Wonnell
Physics and Astronomy Department E-Mail: wonnell@pha.jhu.edu
Johns Hopkins University Phone: (410) 516-4696, 516-5468
3400 N. Charles Street Fax: (410) 516-7239
Baltimore, MD 21218-2686 Office: 478 Bloomberg
************************************************************************
From wonnell@pha.jhu.edu Sun Oct 2 11:48:11 2005

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