Difference between revisions of "Thermal stability"

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The strength of constraint for thermal stability is typically between <br>
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* the stronger requirement of [[chemical stability]] and ...
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* the weaker requirement of [[mechanical stability]].
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== Thermal stability issues are totally not a show stopper ==
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For temperatures at and around room temperature there are many attractive materials (and structures out of these materials) <br>
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that [[for all practical purposes]] do not experience any undesired diffusion atom hopping events.
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Even for significantly higher temperatures (like e.g. what one encounters on Venus ~500°C) <br>
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there are plenty of materials ([[Refractory compounds]] - melting points >2500°C - including cheap [[Moissanite]])
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that still experience insignificant diffusion.
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== What to look out for ==
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Most critical for thermally induced undesired diffusion hop events are:
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* [[Surface diffusion]] (and [[Surface reconstruction]]) – especially crystal edges, steps, and "steps of steps"
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Locatins with high local mechanical tensions like e.g.
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* on grain boundaries from production via [[thermodynamic means]]
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* in step or screw dislocations
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[[Piezochemical mechanosynthesis]] does neither produce grain boundaries nor produce step or screw dislocations <br>
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with high tensions inside them. Well, unless it's done with very deliberate intention. <br>
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Edges and steps can be tailored to the thermal demands. <br>
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'''Some extreme example application cases are:'''
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* Internals of [[rocket engines]]
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* [[nuclear fusion|Fusion]] power plants
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* Mining robotics for [[Venus]]
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* ...
  
 
== Related ==
 
== Related ==
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* [[Refractory compounds]]
 
* [[Refractory compounds]]
 
* [[Diffusion transport]]
 
* [[Diffusion transport]]
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* [[Surface reconstruction]]
 
* [[Thermal damage]]
 
* [[Thermal damage]]
 
* [[Thermal motion]] – [[Brownian motion]]
 
* [[Thermal motion]] – [[Brownian motion]]
* [[Thermodynamics]]
 
* [[Thermodynamic means]]
 
 
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* [[Thermal management in gem-gum factories]]
 
* [[Thermal management in gem-gum factories]]
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* [[Thermodynamic means]]
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----
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[[Common misconceptions about atomically precise manufacturing]] & [[Thermodynamics]]: <br>
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* concerns about thermal motion preventing practical [[piezochemical mechanosynthesis]] or even ...<br>
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* concerns about thermal motion preventing sufficient stability of the synthesized structures <br>
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Neither of these two concerns hold on closer inspection.

Latest revision as of 12:41, 25 July 2021

This article is a stub. It needs to be expanded.

The strength of constraint for thermal stability is typically between

Thermal stability issues are totally not a show stopper

For temperatures at and around room temperature there are many attractive materials (and structures out of these materials)
that for all practical purposes do not experience any undesired diffusion atom hopping events.

Even for significantly higher temperatures (like e.g. what one encounters on Venus ~500°C)
there are plenty of materials (Refractory compounds - melting points >2500°C - including cheap Moissanite) that still experience insignificant diffusion.

What to look out for

Most critical for thermally induced undesired diffusion hop events are:

Locatins with high local mechanical tensions like e.g.

Piezochemical mechanosynthesis does neither produce grain boundaries nor produce step or screw dislocations
with high tensions inside them. Well, unless it's done with very deliberate intention.
Edges and steps can be tailored to the thermal demands.

Some extreme example application cases are:

Related

The three stabilities:




Common misconceptions about atomically precise manufacturing & Thermodynamics:

  • concerns about thermal motion preventing practical piezochemical mechanosynthesis or even ...
  • concerns about thermal motion preventing sufficient stability of the synthesized structures

Neither of these two concerns hold on closer inspection.