Abstract Due to the property of high energy density, temperature and density, the plasma prodced by the coaxial gun is usually untilized to simulate the Type- I ELM in tokamak. In this work, the plasma characteristics of a tapered coaxial gun was studied and its effect on the tungsten target was investigated. By using current probe, photodetector, spectrometer and calorimeter, it is found that the plasma energy density, density and velocity increase obviously with the discharge voltage. The maximum energy density could reach 1.4 MJ/m2, the maximum electron density could reach 3 × 1015 /cm3, and the maximum ion kinetic energy could reach 113 eV at the voltage of 16 kV, which is suitable for simulating the type I Elms in Tokamak. After one shot, there are many cracks and ablative spots on the surface of W target. Whose size could reach ∼ μm by scanning electron microscope(SEM), this is because W material will become brittle after the frequent heating and cooling alternations under thermal shock and the melt motion driven by high plasma pressure gradient. With the Energy Dispersive Spectrometer(EDS), it can be seen that no matter from the cracks and other area of the surface after one shot, the impurity can be ignored. These results help us to better understand the damage effect of tungsten target for further research.

中文翻译：

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锥形同轴枪的等离子体特性及其对钨靶的损伤效应

摘要 由于具有高能量密度、温度和密度的特性，同轴枪产生的等离子体通常被用来模拟托卡马克中的I型ELM。在这项工作中，研究了锥形同轴枪的等离子体特性，并研究了其对钨靶的影响。通过使用电流探头、光电探测器、光谱仪和量热仪，发现等离子体能量密度、密度和速度随着放电电压的增加而明显增加。最大能量密度可达1.4 MJ/m2，最大电子密度可达3×1015 /cm3，16 kV电压下最大离子动能可达113 eV，适合模拟I型Elms托卡马克。一次射击后，W靶表面出现许多裂纹和烧蚀点。其尺寸通过扫描电子显微镜（SEM）可以达到~μm，这是因为W材料在热冲击和高等离子体压力梯度驱动的熔体运动下经过频繁的加热和冷却交替后会变脆。用能谱仪（EDS）可以看出，无论从一次射击后的表面裂纹和其他区域来看，杂质都可以忽略不计。这些结果有助于我们更好地了解钨靶的损伤效应以进行进一步研究。可以看出，无论从一击后表面的裂纹和其他区域来看，杂质都可以忽略不计。这些结果有助于我们更好地了解钨靶的损伤效应以进行进一步研究。可以看出，无论从一击后表面的裂纹和其他区域来看，杂质都可以忽略不计。这些结果有助于我们更好地了解钨靶的损伤效应以进行进一步研究。