Improving weld forming quality and process adaptability by using a copper liner in laser-MAG hybrid overhead welding

Abstract

During overhead welding, gravity inevitably drives the molten pool downward, resulting in poor adaptability and concave defect. To address this issue, this paper proposed a novel laser-MAG hybrid overhead welding technique utilising a copper liner (COL). Compared to single-arc welding, laser-MAG hybrid welding can reduce the volume of the molten pool, while the laser increases its support force. The COL can accelerate the molten pool's solidification rate. Additionally, the adhesion force between the molten pool and the COL can partially counterbalance gravity. As a result, good weld formation still was achieved even when the misalignment was 0–1 mm and the butt gap was 0–2 mm. Moreover, the back reinforcement height and width were not less than 0.71 and 3.66 mm, respectively.

KEYWORDS:

• Overhead welding
• weld morphology
• copper liner (COL)
• process adaptability
• misalignment
• butt gap
• laser-MAG hybrid welding

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Key Research and Development Program of China: [Grant Number 2022YFB4600900] and Liaoning Province Applied Basic Research Program Project [Grant Number 2023JH2/101300157].