The welding characteristics of a new Ni-Cr-Mo alloy designed to resist wet process phosphoric acid

This paper concerns the welding characteristics of a new, high-chromium nickel alloy designed specifically for use in concentrated wet process phosphoric acid, a key chemical in the agrichemical industry. The alloy was also designed to resist chlorides and other oxidizing acids. The study involved use of the Varestraint weldability test, to assess the susceptibility of the alloy to solidification cracking, and evaluation of the mechanical properties of gas tungsten arc and gas metal arc weldments. In addition, the corrosion properties of weldments were determined by immersing all-weld-metal samples of the alloy in a number of acid media. For perspective, this paper also includes Varestraint test data for several well-established, corrosion-resistant nickel-based alloys, and defines the corrosive conditions under which the new alloy excels.