摘要
针对中高压电子束焊机5-100mA的电子束流诊断，完成了法拉第筒传感器的研制。该传感器由法拉第筒、微弱信号放大电路、增益控制电路构成。法拉第筒电极入射孔采用双孔结构，有效的阻止了二次电子和背散射电子的逸出，提高了电子束流的收集效率。通过控制微弱信号放大电路的增益将整个束流强度范围内的信号放大到伏级。在Ua=150kV，b=10mA，If=360mA，H=315Inin条件下采集功率密度分布数据，得到束流密度的二维分布图形。由于受电子束焊机特性的影响，束流功率密度分布呈非对称性的近高斯分布。
A novel type of Faraday cup sensor was developed to diagnose the electron beam, 5-100 mA, in the high voltage electron beam welder. The newly-developed sensor consists of a Faraday cup, a weak signal amplification circuit, and a gain control circuit. The two trapping holes in the Faraday cup significantly improve the efficiency of electron beam collection because few secondary and back-scattered electrons could possibly escape. The signal of any electron beam in- tensity in the full range can be easily amplified to voltage scale. The 2-diensional power density distributions were ac- quired under the conditions： Ua = 150 kV, lb = 10 mA, If=360 mA, and H = 315 mm. The possible mechanisms respon- sible for the asymmetrical Gaussian distribution of the power density were also tentatively discussed.
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2012年第7期649-652,共4页
Chinese Journal of Vacuum Science and Technology
基金
南京理工大学自主科研专项计划资助项目(2010XQTR01)
国家科技重大专项-高档数控机床与基础制造装备项目(2010ZX04007-041)
关键词
电子束焊接
法拉第筒
束流诊断
功率密度分布
Electron beam welding, Faraday cup, Beam diagnostics, Power density distribution
