Difference between revisions of "Consistent design for external limiting factors"

From apm
Jump to: navigation, search
m (absolute maximum/minimum Temperature)
(absolute maximum/minimum Temperature: moved big chunk to new page "refractory materials")
Line 27: Line 27:
  
 
Diamond is metastable and can turn into graphite at too high temperatures.
 
Diamond is metastable and can turn into graphite at too high temperatures.
Other [[diamondoid]] materials like the carbides of the titanium vanadium and chromium group ([//en.wikipedia.org/wiki/Carbide interstitial carbides]) can be used for high temperature applications since they are [http://en.wikipedia.org/wiki/Refractory refractory]. (complete sets of DMEs are needed).
+
Other [[refractory materials]] are better suited for high temperature applications.
Stability of free or mutual or environmentally contacting passivated surfaces (that are possibly strained) will reduce the allowed temperatures well below the bulk material melting points though. Interstitial diffusion may too be a limiting factor.
+
 
+
4th period:
+
* [//en.wikipedia.org/wiki/Titanium_carbide TiC] (3,160 °C; 5,720 °F; 3,430 K; abundant elements)
+
* [//en.wikipedia.org/wiki/Vanadium_carbide VC] (2810 °C; 9-9.5 Mohs)
+
* [//en.wikipedia.org/wiki/Chromium_carbide Cr<sub>3</sub>C<sub>2</sub>; Cr<sub>7</sub>C<sub>3</sub>; Cr<sub>23</sub>C<sub>6</sub>] (1,895 °C; 3,443 °F; 2,168 K; extremely hard; very corrosion resistant)
+
5th period:
+
* [//en.wikipedia.org/wiki/Zirconium_carbide ZrC] (3532 °C; extremely hard; highly corrosion resistant; very metallic)
+
* [http://en.wikipedia.org/wiki/Niobium_carbide Nb<sub>2</sub>C] (3490 °C; extremely hard; highly corrosion resistant)
+
* Mo<sub>2</sub>C (2692 °C) [http://tttmetalpowder.com/molybdenum-carbide-powder-303/]; MoC; Mo<sub>3</sub>C<sub>2</sub> [http://en.wikipedia.org/wiki/Carbide]
+
6th period:
+
* [//en.wikipedia.org/wiki/Hafnium_carbide HfC] (3900 °C; very refractory; low oxidation resistance)
+
* [//en.wikipedia.org/wiki/Tantalum_carbide TaC<sub>X</sub>] (3880 °C (TaC)  3327 °C (TaC<sub>0.5</sub>); extremely hard; metallic conductivity)
+
* [http://en.wikipedia.org/wiki/Tungsten_carbide WC] (2,870 °C; 5,200 °F; 3,140 K; ~9 on Mohs scale)
+
mixed:
+
* [//en.wikipedia.org/wiki/Tantalum_hafnium_carbide Ta<sub>4</sub>HfC<sub>5</sub>] (record holder: 4,215 °C; 7,619 °F; 4,488 K)
+
 
+
Note: Many elements here are neither abundant nor prime targets for [[mechanosynthesis]].
+
  
 
[[Category:Technology level III]]
 
[[Category:Technology level III]]

Revision as of 09:14, 31 May 2014

When designing a product usually one wishes that it poses some resilience to environmental influences. A few critical delicate components in a mainly robust system can bog down the whole system. Those components are the weakest links in the chain and constitute some kind of bottleneck. To avoid disproportionate bog-down components should be paired with their resilience ranges, that is microcomponents could be tagged with links to informations on allowed ranges. This way one can design a system consistently for a chosen set of external limiting factors that one requires. or maximize certain limiting factors.

External limiting factors can be:
temperature T, radiation I , .., acceleration a, pressure p, ...

absolute maximum/minimum Temperature

The allowed temperature range of a whole system (on a thermally equilibrated micro-scale) is defined by the intersection of all the allowed temperature ranges of the system components. When using technology of brownian technology path in e.g. technology level III either in the process of reaching it or when re-merging after reaching it the machine phase (e.g. entropic batteries) AP Technology will acquire an accordingly restricted range of allowed operation temperature range especially much of the otherwise down to zero kelvin completely allowed low temperature regime will be cut off.

It is advisable to keep track off all the allowed temperature ranges for system components (no matter which technology path) and keep the technology path branches (with vastly different allowed temperature ranges) as separate as possible.

Structures to look out for as weak points:

  • highly strained diamondoid molecular elements like cylindric shells
  • structures that form when slightly changed other structures that are known to be highly stable e.g. nitogen rich locations

Diamond is metastable and can turn into graphite at too high temperatures. Other refractory materials are better suited for high temperature applications.