Dc emitting characteristics of single crystal lab6 thermionic cathode 6熱陰極直流發(fā)射特性實(shí)驗(yàn)研究
Scandate cathode has outstanding properties of high emission at low work temperature . it ’ s the only thermionic cathode which can suffice to the development of new electronic device ’ s requirement 含鈧擴(kuò)散陰極具有極其優(yōu)異的低溫高電流密度的電子發(fā)射的能力,是目前唯一能滿足新型電子器件發(fā)展要求的熱陰極材料。
With the development of high power microwave tube , the theoretical and experiment investigation of the high performance cathode have been conducted . the research work includes how to prepare the high performance cathode and the effect of the based metal on the cathode emission , the measurement of the inner and surface fine structures of the cathode , the discussion of emission mechanism of thermionic cathode . after a lot of experiment , we finally determined the cathode preparation with an excellent emission 為了適應(yīng)大功率微波管的發(fā)展,本文展開了對(duì)高性能(大電流密度、長壽命)陰極的研究,研究工作包括陰極制備工藝、鋇鎢陰極基金屬對(duì)陰極發(fā)射性能影響、以及鋇鎢陰極基底內(nèi)部結(jié)構(gòu)無損檢測及表面形貌檢測、鋇鎢陰極發(fā)射機(jī)理探討及應(yīng)用四個(gè)方面的實(shí)驗(yàn)和理論的研究。
However , the most commonly used x - ray sources didn " t change much no matter in structure or theory , still using thermionic cathodes as electron sources . such conventional x - ray tubes have some defaults , such as big volume , low frequency response , demanding for supply to cathode that was also brittle 目前使用的x光源的基本特點(diǎn)是采用熱電子發(fā)射形式即采用熱燈絲作為電子發(fā)射源,在高壓加速下轟擊陽極產(chǎn)生x射線,這樣的光源體積較大,需要加熱陰極的電源,且對(duì)頻率響應(yīng)慢。
As a nondestructive technique to measure the inner fine structure of the cathode , the ict has the unique advantage . we discussed the emission mechanism of thermionic cathode , and tried to explain the excellent performance of mixed metal cathode by richardson formula and muller ' s computational model 4 )就當(dāng)前鋇鎢陰極發(fā)射機(jī)理的兩個(gè)主要理論模型作了自己的探討,并初探了鋇鎢陰極中鋇的供應(yīng)機(jī)制及發(fā)射壽命預(yù)測的問題,而且用理查遜公式的推導(dǎo)和muller計(jì)算機(jī)模擬法解釋了混合基鋇鎢陰極的優(yōu)良性能。