基于DIABEAM法的电子束能量密度测试分析

Electron Beam Diagnostics of Power Density by DIABEAM Method

为了充分发挥电子束焊接技术在航空航天领域的作用,对反映束流品质的关键因素—电子束能量密度开展了研究;基于法拉第传感原理,通过DIABEAM测试法对真空电子束焊机电子束能量密度分布进行测试分析;结果表明:电子束能量密度分布呈非对称的近高斯分布,随着聚焦电流的增加,电子束能量密度趋于发散分布,达到焦点状态时dP90区域内电子束能量密度均值最高;电子束能量密度峰值随着灯丝加热电流增加而增加,但受灯丝尺寸等因素的影响,灯丝加热电流达到稳定值后能量密度分布不变。

The electron beam power density distribution in electron beam welding （EBW） was measured by DIA- BEAM method, based on Faraday sensing principle, to widen its applications in aerospace industry. The results show that the electron beam power density distribution can be approximated as an unsymmetrical Gaussian, and that as the focusing current increases, the power density tends to disperse, peaking in the dp90 zone of the focus state. In addition, the peak of the electron beam power density rises up with an increase of the resistive heating current of the filaments, reaching a steady state after the current was finally stabilized.