The present contribution is the first research reporting full penetration HLAW joints in 15 mm thick EH36 steel butt T-welds with square grooves on 2F welding position by single-sided welding. The effects of welding parameters were investigated to increase the quality of the joints. Conditions leading to defect-free full penetration welds fulfilling naval regulations includes a laser power of 12.5 kW, a welding speed of 1.6 m/min and the vertical laser offset distance from the flange of 1 mm. Advanced characterization of selected welds included a microstructural identification by optical microscopy, SEM, and XRD, revealing the presence of acicular, polygonal and Widmanstätten ferrite, lath martensite, and some retained austenite at FZ. Hardness and microhardness mapping tests showed values of 155 HV at base metal and 200 to 380 HV at the fusion zone connecting the web to the flange.

中文翻译：

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HLAW参数对15 mm厚度海军钢的一侧T型接头的影响

目前所做的贡献是第一项研究，报告了在2F焊接位置通过单面焊接在15毫米厚的EH36钢对接T形焊缝上进行全熔透HLAW接头的过程，该焊缝带有方槽。研究了焊接参数的影响，以提高接头的质量。导致无缺陷的全熔透焊缝满足海军法规的条件包括12.5 kW的激光功率，1.6 m / min的焊接速度以及垂直于法兰的激光偏移距离1 mm。选定焊缝的高级表征包括通过光学显微镜，SEM和XRD进行的显微组织鉴定，揭示了针状，多边形和Widmanstätten铁素体，板条马氏体以及在FZ处残留的奥氏体的存在。