中文摘要：

采用光纤式光谱仪,对激光—MAG复合焊等离子体辐射,进行空间分布200～1100nm间光谱采集。选取特定谱段辐射积分,给出其在紫外辐射（FeII）、可见光辐射（FeI）、红外辐射（ArI）各扫描层面辐射强度分布。进一步结合高速摄像,研究激光—MAG复合焊的耦合机理。研究结果表明,激光与MAG复合后,其等离子体在焊接电弧中心位置的辐射增强（其中紫外和可见光谱段更明显）,形成一个辐射梯度较大的辐射增强区。FeI、FeII对应谱段的电弧辐射区间增宽,这种现象在激光作用的电弧前沿更明显。特定谱段辐射的面分布表明,激光—MAG耦合后,辐射在熔池附近及电弧中部的辐射增强,而在电弧上部的辐射减弱。耦合后的等离子体能量分布更集中于中心部位和熔池附近,复合等离子体Fe辐射区间的增宽,也为电弧稳定提供电离通道。耦合后等离子体辐射分布,使得激光复合焊焊缝成形改善、电弧稳定性增加。

英文摘要：

The radiation of laser-MAG hybrid welding plasma is collected with fiber spectrometer.The spatial distribution of spectra from 200 to 1 100 nm is studied and spectral bands are selected.The selected spectral bands include ultraviolet radiation（Fe II dominated）,visible radiation（Fe I dominated） and infrared radiation（Ar I dominated）.The radiation in the selected spectral bands is acquired to compare the radiation intensity of different scanning surface.Furthermore,high speed video is also applied to studying the coupling of laser-MAG hybrid welding plasma.The result shows that there is a high radiation intensity zone with great gradient in the center of laser hybrid welding plasma.The spectral bands of FeI and FeII have a broader radiation range for laser-MAG welding.This is significant near the laser focusing position.The radiation increases in the middle and lower part of the plasma,especially near the welding pool.However,it decreases in the upper part of welding plasma.The welding process with laser hybrid will cause the plasma energy to focus on the center of welding arc and the welding pool.The broader radiation range of Fe ion provides ionizing duct for welding arc,thus makes the welding arc stable.The coupling effect provides better bead formation and more stable arc in the laser-MAG hybrid welding process.