摘要
介绍了自行研制的用于闪光照相且基于感应电压叠加器和阳极杆箍缩二极管的X射线源的组成、结构和主要参数。输出电压3 MV的Marx发生器给阻抗7.8Ω水介质脉冲形成线充电,产生脉宽约70ns,电压约1 MV的高功率脉冲,经过峰化开关和预脉冲开关后分成3路馈入三级感应电压叠加器感应腔进行电压叠加,感应电压叠加器次级采用真空绝缘传输线,阻抗从40Ω变成60Ω,驱动阳极杆箍缩二极管,二极管阴极为石墨,阳极为直径1.2 mm的钨杆,石墨阴极产生的电子束在电流自磁场作用下发生箍缩,轰击阳极,产生小焦斑脉冲X射线。该装置在Marx充电电压为±35 kV时,二极管电压约2.0 MV,二极管电流约为50kA,半高宽约80 ns;X射线半高宽约为40 ns,剂量约为28 mGy,焦斑约为0.95 mm。利用该X射线源拍摄到了炸药爆炸产生的层裂碎片不同飞行时间的图像。
The pulsed X-ray source based on the inductive voltage adder(IVA) and rod pinch diode(RPD) is developed,and its configuration and main parts and output parameters are introduced in detail.The Marx generator with 3.3 MV charges the water pulsed forming lines with 7.8 Ω and produces the high power pulse of 70 ns width with about 1 MV feeding the three IVA cells in parallel through the peaking water switch and the pre-pulse oil switch.The secondary of IVA adopts the vacuum insulation transmission line(VITL) with the impedance from 40 Ω up to 60 Ω,driving the RPD isolated from the output terminal of IVA for 2 m VITL.The diameter of the graphite cathode of RPD is 12 mm,and the diameter of the tungsten anode rod is 1.2 mm.The electron beam from the cathode is pinched to the tip of the anode rod by the electric-magnetic force of the current and emits the pulsed X-ray with small focus spot.When the Marx generator is charged positive/negative 35 kV,typical parameters of RPD are voltage of about 2.0 MV,current of about 50 kA and full width of half magnitude(FWHM) of 80 ns,and the X-ray parameters are FWHM of about 40 ns,dose of 28 mGy and focus spot diameter of 1 mm.The radiographic images of the spalls of Fe and W material produced by explosion are obtained with the developed X-ray source.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2010年第4期936-940,共5页
High Power Laser and Particle Beams
基金
国家自然科学基金项目(50477019
50637010
10775112
19975037)