Difference between revisions of "Consistent design for external limiting factors"
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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 [[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). | ||
| − | Stability of free or mutual or environmentally contacting passivated surfaces will reduce allowed temperatures well below the bulk material melting points though. | + | 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: | 4th period: | ||
Revision as of 16:39, 12 January 2014
External limiting factors can be:
- thermal
- radiation
- acceleration
- pressure
Microcomponents could be tagged with links to informations on allowed ranges.
thermal
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.
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 (interstitial carbides) can be used for high temperature applications since they are refractory. (complete sets of DMEs are needed). 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:
- TiC (3,160 °C; 5,720 °F; 3,430 K; abundant elements)
- VC (2810 °C; 9-9.5 Mohs)
- Cr3C2; Cr7C3; Cr23C6 (1,895 °C; 3,443 °F; 2,168 K; extremely hard; very corrosion resistant)
5th period:
- ZrC (3532 °C; extremely hard; highly corrosion resistant; very metallic)
- Nb2C (3490 °C; extremely hard; highly corrosion resistant)
- Mo2C (2692 °C) [1]; MoC; Mo3C2 [2]
6th period:
- HfC (3900 °C; very refractory; low oxidation resistance)
- TaCX (3880 °C (TaC) 3327 °C (TaC0.5); extremely hard; metallic conductivity)
- WC (2,870 °C; 5,200 °F; 3,140 K; ~9 on Mohs scale)
mixed:
- Ta4HfC5 (record holder: 4,215 °C; 7,619 °F; 4,488 K)
