Welding current influences on Inconel 625/X65 cladding interface

ABSTRACT

The pulsed gas tungsten arc welding with hot wire was used to clad Inconel 625 on the surface of X65 steel. The influences of welding current in horizontal welding position on the dilution, in further the composition, microstructure, and property of the Inconel 625/X65 cladding interface were investigated. Experimental results show that with the increase in welding current, namely, in heat input and arc force, dilution rate increased; the composition transition region in the cladding layer close to the fusion line, controlled by the cladding temperature, would be widen; in further, the microstructure would be different due to the heat transfer and composition change; the precipitates were niobium-rich MC carbide with a low welding current, but tended to be the intermetallic compounds, Laves phase, with a high welding current; the highest and lowest hardness values appeared on the heat-affected zone and cladding layer next to the bonding interface, respectively.

KEYWORDS:

• Clad
• current
• diffusion
• dilution
• hardness
• Inconel
• microstructure
• precipitate
• welding

Additional information

Funding

This research is supported by National Natural Science Foundation of China (Grant No.: 51505326), Natural Science Foundation of Tianjin (Grant No.: 16JCQNJC04300), and Innovation Fund of Tianjin University. We would like to thank the financial support from Offshore Oil Engineering, Co. Ltd.