Practical constraint condition of hull structural members for application of laser-arc hybrid welding to the hull construction process

2015 Fiscal Year Final Research Report

• Project/Area Number: 26630458
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Naval and maritime engineering
• Research Institution: Kyushu University
• Principal Investigator: Gotoh Koji 九州大学, 工学(系)研究科(研究院), 准教授 (60274487)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: レーザ・アークハイブリッド溶接 / 溶接施工条件 / 仮付け溶接

Outline of Final Research Achievements

Laser-arc hybrid welding technology, which has the advantages of laser and normal arc welding, provides high-quality welds and is expected to improve productivity and accuracy. A strong advantage of laser-arc hybrid welding is its low heat input compared with conventional arc welding. Large reductions in residual welding deformation are expected when applying laser-arc hybrid welding. Such improvements will increase the productivity of hull construction and permit structural styles that reduce the net weight of a hull. Meanwhile, the large-scale constraint device of members must be equipped in the laser-arc hybrid welding systems to fabricate high quality welded joints.
New tack welding procedure, which laser irradiation without filler wire was applied to melt the region of connection to fix between the stiffener and base plate, is proposed and verified by macroscopic observation of weld bead appearance and cross section, measurement of angular distortion and fatigue tests.

Free Research Field

船舶海洋工学