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ASTM F83-71(2018)

Отменен
Standard Practice for Definition and Determination of Thermionic Constants of Electron Emitters (Withdrawn 2023) — 6 стр.
Причина отмены This practice covered the definition and interpretation of the commonly used thermionic constants of electron emitters with appended standard methods of measurement.

Formerly under the jurisdiction of Committee F01 on Electronics, this practice was withdrawn in November 2023. This standard is being withdrawn without replacement because Committee F01 was disbanded.

Реферат

This practice covers the definition and interpretation of the commonly used thermionic constants of electron emitters with appended standard methods of measurement. Cathode materials shall alternatively be evaluated by relating the temperature-limited emission to fundamental properties of the emitter, particularly the work function. Comparisons are made between emitters using the thermionic constants such as the work function, emission constant, and the temperature dependence of the work function. These thermionic constants are geometry and field effects-independent, but exhibit variations under different conditions. The pertinent equations the Richardson-Dushman equation of electron emission to evaluate the effective work function, which in turn, shall be used to find the Richardson work function and the true work function. Sample computations are also detailed.

Область применения

1.1 This practice covers the definition and interpretation of the commonly used thermionic constants of electron emitters (1, 2, 3),2 with appended standard methods of measurement.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ICS
01.040.31 Electronics (Vocabularies) / Электроника (Словари)
31.100 Electronic tubes / Электронные лампы
Сборник ASTM
10.04 Electronics; Declarable Substances in Materials; 3D Imaging Systems; Additive Manufacturing Technologies / Электроника; Декларируемые вещества в материалах; Системы 3D-визуализации; Аддитивные технологии производства
Тематика
Electronics