脉冲金属氢化物真空弧放电等离子体发射光谱特性

Spectral property investigation of pulsed metallic hydride vacuum arc discharge plasmas

利用发射光谱方法对真空弧离子源放电等离子体特性进行了诊断。同时,基于局域热力学平衡等离子体的发射光谱理论,建立了等离子体的发射光谱拟合模型,对真空弧放电等离子体光谱进行了分析。针对TiH真空弧离子源,分别对330-340nm与498-503nm范围内Ti＋离子与Ti原子的发射光谱进行了对比拟合,获得了较好的符合度,解决了传统Boltzmann斜率法计算等离子体温度需要孤立的不受附近谱线干扰的线状光谱的困难。最后,利用该方法计算了真空弧离子源在不同放电条件下的等离子体发射光谱、等离子体密度与温度参数。结果表明,TiH真空弧放电等离子体温度在1eV左右,同时,放电所产生的氢原子要远远大于金属原子,并且随着真空弧离子源馈入功率的增加,TiH电极中解吸附出来的氢比蒸发出来的金属增加得更多,这有利于TiH离子源在中子发生器方面的应用。

An optical emission spectroscopy method had been applied to diagnose titanium hydride vacuum arc discharge plasmas.Based on the emission spectra theory of the local thermodynamic equilibrium plasma,aplasma emission spectral fitting model was developed to analyse the emission spectra of the vacuum arc discharge plasmas.Comparing the fitting spectral and the observed spectral in the region of 330-340 nm and 498-503 nm respectively,good agreement was found between the predicted and observed spectra.Since this model calculated the summation of Voigt profiles of all spectral lines in the concerned range,it overcame the extraction of intensity and broadening from the overlapped lines by conventional Boltzmann plot method.Furthermore,the emission spectra,density,and temperature of the vacuum arc discharge plasmas under different discharge conditions were studied.The results indicated that the temperature of the TiH vacuum arc discharge plasmas were about 1eV,and the generated hydrogen atoms were more than the titanium atoms.At the same time,with the increasing feed-in power to vacuum arc ion source discharge,more hydrogen atoms were desorbed from the electrode than the electrode metal atoms erupted,which was benefit for the application of neutron generator.