为了促进船用高强钢E36激光焊接技术的发展，利用YAG激光器对3.2 mm厚的E36钢板进行对接焊接处理。分析了焊接接头的微观组织形貌与硬度特性；研究了焊接速度对接头性能的影响。结果表明，E36钢激光焊缝(WZ)金属主要由马氏体构成，其硬度高于母材(BM)。焊接接头硬度分布不均匀，在焊缝边缘有着最高硬度；热影响区(HAZ)很窄，且硬度急剧下降。随着焊速变化焊接接头的性能以及硬度特性也发生变化：当焊接速度达到70 mm/s时，焊缝区域的最高硬度达到448.9HV，为所有试样中最高，而其热影响区硬度值下降最快。在垂直于焊缝的负载下，焊接速度为20~60 mm/s的拉伸试样均断裂在母材，而焊接速度为70 mm/s的试样却断在熔合线附近，塑性明显差于断在母材的试样。

It is important to accelerate the development of the laser welding technology of marine high strength steel E36. Laser butt welding of 3.2-mm thick E36 is performed by using a YbYAG laser. The microstructure and hardness of weld joints are analysed and the effects of the welding speed on properties of the weld joints are studied. The result shows that the microstructure of weld zone (WZ) is mainly martensite, and the microhardness of WZ is higher than that of base metal (BM). The hardness distribution of weld joint is non-uniform. The weld edge has an highest hardness. Heat affected zone (HAZ) is very narrow and the hardness in this zone drops quickly. With the increase of the welding speed, the properties and microhardness also change: When the welding speed is 70 mm/s, the highest hardness of the WZ is 448.9 HV, which is the highest of all the samples, and the hardness in its HAZ drops most quickly. The tensile samples which are welded at speed from 20 mm/s to 60 mm/s are all broken in base metal. When the welding speed is 70mm/s, the samples are all broken in fusion line and its ductility is obviously worse than that broken in base metal.