【摘要】 轰击式LaB6阴极是一种电子枪的新型阴极,它不仅具有良好的电子光学系统结构,而且电子发射能力强大,对大功率电子枪的研制和开发有着重要意义.论述了新型轰击式LaB6阴极的工作原理、研究的意义、阴极材料的选择,并完成了轰击式阴极的设计和计算,设计完成了轰击式LaB6阴极的实验装置.通过实验得到,该轰击式LaB6阴极在阴极温度为1843K时具有最大发射电流450mA,其发射电流密度为3.58A/cm2.列举了典型试验数据并进行分析,得到所选用的LaB6的发射常数A为21.33,逸出功Φs为2.6eV,这与理论值非常接近,证明了试验的准确性和可靠性,该试验结果为大功率电子枪的开发研究、为大功率电子束焊接设备研制奠定了基础.更多还原

【Abstract】 The bombardment LaB6 cathode is a new type of cathode, applied in the electron gun. It has not only a good structure in optic system but also powerful ability of emission, being of great significance in developing and researching the highpower electron gun. The working principle, significance of the study, and selection of material far the cathode are discussed in detail, and the design and calculation of bombardment and its experimental equipment are fulfilled. It is found by the experiment that the bombardment LaB6 cathode could possess maximum current emission of 450 mA, if the cathode temperature were 1 843 K. Moreover, by analyzing the data of the experiment, we got the constant A of LaB6 emission being 21.33 and its escaping work ΦS being 2.6 eV, which are quite close to the theoretic values, so that the experiment is proved to be accurate and reliable, providing a basis for developing and researching the cathode of the highpower electron gun and electron beam welding equipments.更多还原