Welding of Nickel Base Hydrochloric Acid Corrosion

Abstract

A new nickel base hydrochloric acid resistsnt alloy has been developed and welding tests were performed on this alloy.
The compositions of the new hydrochloric acid resistant alloy named HZ Alloy CL were molybdenum 25, tungusten 3, copper 1, iron 1, titanium 0.2 weight % and nickel balance.
Coated flux compositions of low hydrogen type on the new alloy electrods were determined. Using this newly developed alloy electrods coated with the flux, Hastelloy C plates were welded by direct current. These weld joints had over 75 kg/mm² in tensile strength, and over 25% in elongation as welded.
The new alloy plates were welded with the new alloy filler metal by TIG arc welding. The tensile strength of the weld joints was a little higher than that by the new alloy electrodes and elongation was almost the same as that by the new alloy electrodes. These deposited metal had almost the same hydrochloric acid resistance as the new alloy plates and casting. In welded parts, there were not observed precipitated second phases which deteriorated the ductility of metals.