Superelasticity

The term gemstone superelasticity or crystolecule superelasticity will be used on this wiki for the unusually high bendability/strainability of flawless nanoscale gemstone machine parts manufactured by advanced forms of mechanosynthesis. In short: The unusually high bendability of Crystolecules.

(Not to confuse with Pseudoelasticity [1] e.g. found in some nickel titanium alloys - known as nitinol.)

Details

The basic building blocks for gemstone based nanomachinery are Crystolecules. They have an extremely low probability of containing at least one flaw like e.g. a misplaced atom. This is due to them being produced via advanced force applying mechanosynthesis. A digital process. Just like bit errors can be pushed to extreme rarity in digital data processing atom placing errors can too. (There are several ways to optimize for low error rate -- see dedicated page).

This flawlessness has the very desirable side effect that there are no unplanned spots where trapped non-relaxed pretension stresses reside and further stresses can concentrate and where cracks can start. Consequently mechanosynthesized crystolecules and flawless nano-gemstones can withstand very big strains (two digit percentage range) that are not possible with gemstones at the macroscopic scale. Such high strains are especially not possible with natural gemstones or todays (2018) thermodynamically produced synthetic gemstones.

Retaining high straibanility to the macroscale

Mechanosynthesized macroscopic slabs of gemstones (which may be quite a bit more difficult to make than crystolecules btw (wiki-TODO: elaborate)) may start out flawless but very quickly acquire flaws from all kinds of radiation (UV, gamma, ...) even when heavily shielded (neutrinos).

To retain extreme strainability as much as possible to the macroscale one can start to build things by interlocking crystolecules in smart ways (see: Shape locking). Cracks of broken crystloecules are instantly stopped and can't propagate any further.

Fractal resilience designs can further increase resilience against failure (see: Motor-muscle).

Measuring Superelasticity

Very small crystals can have flawless structure even when produced thermodynamically today. This may provide a way to test superelasticity experimentally today. But this seems difficult. For compression maybe one could clamp a crystal with a super-hard monocrystalline nanoscale vice? But what would one do for tension? (TODO: check if there where experiments testing superelasticity)

(Sidenote: Thermodynamic synthesis of nanoscale gemstones gives almost no control of outer shape, internal strains and heterogenity. One usually gets an unstrained homogeneous crystal lattice with crystal faces in the directions of slowest growth. So crystolecules cannot be made that way. Unfortunately.)

Quantitative

Nanosystems Chapter 3.3.3. Energy, force, and stiffness under large loads
Subchapter a. Bonds under large tensile loads.

Parge 52 Table 3.8.
For C–C r_0 = 0.1523nm

Page 53,5:
"… the Morse function grows increasingly inaccuratte far from the equilibrium separation. For a structural perspective, the shape of the Morse function is of interest chiefly withing the separation defined by the inflection point, r = r_0 + (ln 2)/ beta; a morse bond stetched beyond this length by a position independent force becomes mechanically unstable (for C–C, at ~0.187nm). Beyond the inflection point the stiffness becomes negative, …"

So from this we glean about the bond fracturing length:
r_max = ~0.178nm

178pm/152.3pm = 116.9%
Thus we get about 15% bond bendability.
For diamond a bit more as bonds go zig-zag adding bond bending flex.
Ti stray well on the safe side 10% is a good estimate.

Page 54 Fighre 3.4. Shows the curves.
(wiki-TODO: Explain curves)

Misc notes

(TODO: Investigate the effect of isotope mixtures on superelasticity.)

Related

• High pressure
• The defining traits of gem-gum-tec
• Crystolecules
• Gemstone based metamaterial ("gem-gum")
• Stiffness
• Superlubrication ... another performance parameter that can be unusually elevated at the nanoscale

External links

(wiki-TODO: Add some examples of the by now 2018 existing experimental verifications of the effect. (diamond and sapphire))