Chludzinski Mariane, Dos Santos Rafael Eugenio, Ortega-Iguña Marta, Churiaque Cristina, Porrúa-Lara Manuel, Sánchez-Amaya José María
Department of Materials Science and Metallurgical Engineering and Inorganic Chemistry, School of Engineering, University of Cádiz, Av. la Universidad de Cádiz, 10, E-11519 Puerto Real, Cádiz, Spain.
Navantia S.A., S.M.E., Bahía de Cádiz Shipyard, Industrial Estate s/n, E-11519 Puerto Real, Cádiz, Spain.
Materials (Basel). 2022 Nov 3;15(21):7741. doi: 10.3390/ma15217741.
Root pass is a fundamental step in multi-pass welding. In gas metal arc welding (GMAW), the weld bead qualities depend on the process parameters, filler materials, and welder abilities. This work investigates the effect of a Nd: YAG pulsed laser as a first pass to reduce the welders' reliance on the AH36 low-alloy steel with 5.5 mm thickness. This autogenous automatable process delivers reduced thermal impact due to the concentrated high-energy source, pulse overlap, and higher penetration depth-to-power ratio than continuous lasers. The outcomes indicate that the PL as a root welding generated a small HAZ compared to the GMAW condition. In addition, the subsequent arc passes positively affected the microstructure, reducing the hardness from around 500 to 230 HV. The PL + GMAW achieved similar strength results to the GMAW, although its Charpy impact values at -50 °C were around 15% lower than the arc condition.
打底焊道是多道焊中的一个基本步骤。在熔化极气体保护电弧焊（GMAW）中，焊缝质量取决于工艺参数、填充材料和焊工技能。本研究探讨了Nd:YAG脉冲激光作为第一道焊道的效果，以减少焊工对厚度为5.5mm的AH36低合金钢的依赖。这种自熔且可自动化的工艺由于集中的高能源、脉冲重叠以及比连续激光更高的熔深与功率比，从而产生了较小的热影响。结果表明，与GMAW条件相比，采用脉冲激光进行打底焊时产生的热影响区较小。此外，后续的电弧焊道对微观结构产生了积极影响，将硬度从约500 HV降低至230 HV。尽管在-50°C时，脉冲激光+GMAW的夏比冲击值比电弧焊条件下低约15%，但其强度结果与GMAW相似。
