Gas tungsten arc welding of copper to stainless steel for ultra-high vacuum applications

Autor: Jitrin Chaiprapa, Anuchit Ruangvittayanon, Supan Boonsuya, Samrerng Duangnil, Yingyot Poo-arporn, Channut Huasranoi, Piyawat Pruekthaisong, Denchay Bamrungkoh, Chatree Saisombat, Pheemphat Klangkaew
Rok vydání: 2020
Předmět:
Zdroj: Journal of Materials Processing Technology. 277:116490
ISSN: 0924-0136
DOI: 10.1016/j.jmatprotec.2019.116490
Popis: The GTAW method was employed for the dissimilar joining of OFHC copper and AISI 304 stainless steel. The special weld joint design of a modified socked-weld flange with edge joints made on short-flanged edges was used. The butt joint of the flange edges was designed to have different height and thickness. The welding was done without filler metal using a DC current of 80 A with pre-heating of the joint at 200 °C. The cross-sectional image of the specimen clearly indicated the fusion zone as a semicircular-shaped bead with the molten region about 0.7 mm from the top. The micro XRF mapping image revealed the heterogeneous elemental distributions of Cu, Fe, Cr, Ni and Mn in the fusion zone. The highest Mn concentration appeared in the Cu-rich area. At the interface, SEM images show the formation of small granules of Fe on the Cu side while the dendrites form near stainless steel. The structures of Fe and Cu were not changed during the welding process as determined by the XAS.
Databáze: OpenAIRE