Multi-Pass Laser and Hybrid Laser-Arc Narrow-Gap Welding of Steel Butt Joints

Abstract

Multi-pass laser and laser-arc narrow-gap welding make it possible to obtain high-quality butt joints of large-thickness pipe steels with hardness up to 2600...2800 MPa and toughness close to the base metal toughness at a temperature of 20°C. When multi-pass welding methods are used, the subsequent pass makes heat treatment of the previous ones, and reduces the rate of their cooling yet. This allows excluding heat treatment of the joint after welding, which significantly reduces the time and costs for manufacturing large-sized structures.

Review of scientific works dedicated to study of influence of component processes of laser and hybrid laser-arc welding on formation of structure and level of mechanical characteristics of welded joints of structural steels

“…Тим не менш, не вдалося уникнути проростання кореня із внутрішньої сторони шва, що необхідно при односторонньому доступу та відповідає випадку застосування й волоконного лазеру 19 . Випробування, які наведені в роботах 20,21 з високоміцною сталлю Optim 960QC проводили з використанням кількох процесів зварювання: дугового зварювання, лазерного, і гібридного лазернодугового зварювання. Були використані лазерні джерела живлення, такі як СО2-лазер, твердотільний дисковий лазер і волоконний лазер.…”

“…Lappeenranta: Finland. 21 Laitinen R., Lehtinen M., Kujanpää V. Fellman A. Influence of laser and hybrid laser-MAG (hybrid) welding on the strength and toughness of the weld HAZ of ultra high strength steel optim RAEX 960 QC.…”

Laser Welding of Ti–Ni Shape Memory Alloy for Medical Application

“…Specialists of the E. O. Paton Electric Welding Institute, N.A.S. of Ukraine have significant experience in performing technological research in laser welding [25][26][27][28][29][30].…”

The Influence of Oscillation Parameters on the Formation of Overhead Welding Seams in the Narrow-Gap GMAW Process

“…After the narrow-gap three-wired indirect arc, a tungsten electrode arc was used, making the convex shape of the weld surface change into a concave shape. The method of electromagnetic controlled pool welding (ECMP) was proposed by the University of Ryukyu in Japan [21] to obtain an ideal joint in the flat position; Shelyagin [22], Wahba [23], Yu [24] and others [25] have studied the process method of laser arc hybrid welding in the flat position. For narrow-gap welding, research on specific methods, such as optimizing the parameters of the welding process, oscillating arc, rotating arc, multi wire welding, and composite welding [26,27] has greatly optimized weld formation and improved welding efficiency.…”