Laser Hybrid Butt Welding of Large Thickness Naval Steel

Cristina Churiaque,Mariane Chludzinski,Francisco Abad-Fraga,Antonio Dominguez-Abecia,Manuel Porrua-Lara,Jose Sánchez-Amaya

doi:10.3390/met9010100

Abstract

Plates joining is one of the first stage at large vessels manufacturing line, process conditioning the whole shipbuilding production. Laser Arc Hybrid Welding (LAHW) process is nowadays providing promising results for large thickness naval steel, being primarily used for welding plates with thicknesses between 6 to 15 mm, reaching up to 51 mm. In addition to this high penetration ability, LAHW allows increasing the production rates. Therefore, this technology is proposed as an alternative to conventional welding processes in shipbuilding, as it integrates the advantages of laser and arc welding, providing high process stability, high welding speed and penetration, narrow weld beads with a low heat input and good metallurgical properties. The present review reports the most representative investigation regarding the use of this technology to join large thickness flat panels of naval steel. It includes a summary of the most influential process variables, equipment characteristics, material properties, naval regulations, as well as microstructural characterisation and mechanical properties of joints. This review is thought to help readers from different backgrounds, covering from non-expert on welding or on naval sector, to industrial LAHW applicators and researchers. The industrial need of performing one single pass procedure to assure high quality welds of high thickness is suggested as one of the key aspects for future investigations.

Highlights

In the laser-arc hybrid welding process (LAHW), the laser beam and electric arc interact together in the weld pool and their synergistic effect is used to perform deeper and narrow welds (Figure 1), increasing the production rate [1,2]
All researches aim to develop welding procedures producing joints able to pass the industrial qualification processes and the approval required by standards
The results demonstrated the better outcomes obtained in all welding zones in comparison with the base materials, with an increase ranging from 32 to 60%

Summary

Introduction

In the laser-arc hybrid welding process (LAHW), the laser beam and electric arc interact together in the weld pool and their synergistic effect is used to perform deeper and narrow welds (Figure 1), increasing the production rate [1,2]. Laser welding has gained popularity in recent years because laser beam focuses energy in a very small area [3]. The precision and concentration of energy provided by laser beam increases the welding speed, which in turn reduces the heat input and the thermal distortion in the welded parts [4]. Most conventional laser systems do not have sufficient electrical efficiency for welding, besides being more expensive. Laser welding has little capacity for bridging or filling the gap and requires great precision in the assembly of workpieces and preparation of edges [5]. The application of laser welding to highly reflective materials such as aluminium, copper, or gold is complex

Methods

Results

Conclusion