How To Weld Inconel 600?

How to weld Inconel 600?

Welding Characteristics of Inconel 600
Generally, preheating is not required for Inconel 600 welding. However, when the base metal temperature is lower than 15 degree , the joint area of two sides with a length of 250 mm ~ 300 mm shall be preheated to 15 degree ~ 20 degree to avoid blow holes resulting from moisture condensing. In order to prevent the grain growth and carbide precipitation, inter-pass temperature shall be no higher than 100 degree . Cautions shall be taken to prevent rapid cooling which may result in porosity. The welding area shall be carefully cleaned before welding operation.

Due to the poor flowability of molten nickel alloy, the slope of bevel ends in jointing area shall be sharp. The welding pool of Inconel 600 is comparatively shallow which may result in incomplete penetration. Medium intensity of welding current and rapid welding are recommended. The coefficient of linear thermal expansion of Inconel 600 is high and it is quite susceptible to hot cracking. Thus, heat input during the welding shall be rigorously controlled.

Welding methods and electrode selection for Inconel 600:

Shielded Metal Arc Welding (SMAW): AWS 5.11 ENiCrFe-3, Φ4.0 mm; Actual chemical composition of ENiCrFe-3 (%): C-0.087, Si-0.77, Mn-6.60, S-0.005, P-0.015, Cr-17.00, Ni-66.70, Mo-0.07, Cu-0.09, Nb-1.69.
Tungsten Inert Gas Welding (TIG): AWS 5.14 ERNiCr-3, Φ2.0 mm; Actual chemical composition of ERNiCr-3 (%): C-0.046, Si-0.30, Mn: 5.50, S: 0.004, P-0.005, Cr-15.62, Ni-64.26, Mo-0.09, Cu-0.02, Nb-1.66.