Corrosion Resistance of Welds

One of the most important product forms of ULTIMET® alloy is welding wire, since many applications involve ULTIMET® weld overlays. These overlays are, of course, subject to dilution from the substrate material, often a steel or stainless steel. To provide some idea of the influence of dilution upon the corrosion resistance of ULTIMET® weld overlays, a study was undertaken whereby pre-diluted consumables were made by the aspiration casting process, and all-weld-metal (AWM) samples made by deposition on chilled copper blocks. Thus, it was possible to conduct regular (rather than one-sided) corrosion tests in acid solutions on homogeneous samples, diluted with specific substrate materials.

ULTIMET® Alloy Corrosion Rate, mm/y
3% HCl, 66°C (150°F) Boiling 65% HNO3 Boiling 2% H2SO4
Undiluted 0.68 0.15 0.41
Diluted with 9.1%/G10400 1.80 0.30 0.69
Diluted with 9.1%/S31603 1.42 0.25 0.58
Diluted with 16.7%/G10400 2.13 0.30 0.84
Diluted with 16.7%/S31603 2.08 0.23 0.48