The analysis of shielding gases in laser–arc hybrid welding processes

Abstract

Acceptable quality laser–arc hybrid welds can be produced with many different process gas compositions, but if the objective is high productivity, low gas costs, a reliable process, and the best quality, the shielding gas composition makes a remarkable difference in the laser–arc hybrid welding of steels. The present paper mostly concentrates on the welding of steel. The gas type used in such processes has a significant influence upon plasma formation, process stability, and the weld bead shape. In this paper, different process gases have been studied in various laser–arc hybrid welding processes. The aim of the review is to assess the influence of shielding gases in the production of a weld. It was concluded from the study that for the constant combination of the laser beam and arc sources, there should be an optimal combination and composition of types of shielding gases. The flowrate of the shielding gas must change the laser-induced plasma plume in order to attain a high coupling coefficient between the laser and the material. The study is based on a critical literature analysis of the results from a variety of studies carried out by several research groups. The effects of parameters and set-up are detailed in the analysis, which especially assesses the economic feasibility and quality management factors.