Gas Metal Arc Welding Process for Surfacing Aluminum Alloys With Al--Cu Cored Wire--Surfacing on Aluminum Alloy. I

• Published in: Yōsetsu Gakkai ronbunshū Vol. 10; no. 4; pp. 59 - 65
• Main Authors: Kanbe, Y, Nakada, Y, Kurihara, S, Koike, H, Miyake, T
• Format: Journal Article
• Language: Japanese
• Published: 01.11.1992
• ISSN: 0288-4771

Surfacing on Al (JIS H4000, A1050P) has been investigated by gas metal arc welding (GMAW) process using a newly developed Al--Cu seamless type cored electrode wire of 1.2 mm in diameter. Two types of cored wires were tested, one was copper sheath type with aluminum solid wire as inside core, and the other Al sheath type. Their chemical compositions were both 30Al--70Cu. Investigations were performed on metal droplet transfer phenomena, microstructure, and hardness distribution vs. arc current, effect of weld heat input on porosity formation, and analysis of H gas from porosities. The Cu sheath cored wire showed far superior quality to the Al sheath. It has excellent arc stability, uniform and stable metal transfer, and uniform hardness distribution in the surfacing weld metal. The overlay hardness 220-280 HV decreased with increasing weld heat input. Hydrogen gas causes porosity formation, which is reduced by increasing weld heat input readily to a low level of total area 1% in transverse cross section of surfacing weld metal. The porosities were very small in size, mostly < 0.2 mm in diameter. Oxygen also seems to cause porosity formation.