Corrosion Fatigue of Nickel and Nickel-Base Alloys

Abstract

Abstract The fatigue properties of commercially pure nickel, Ni-28Mo alloy, and Ni-16Cr-16Mo-4W alloy are established in air. The fatigue properties of nickel are affected by exposure to aqueous environment. The approximate fatigue life of nickel in air is reestablished upon increasing the pH. A corrosion fatigue critical current density of ≃1.2 µA/cm2 is determined for nickel in deaerated 4% NaCl solution. The Ni-28 Mo alloy suffers corrosion fatigue damage in 4% NaCl solution and in deionized water. The passive Ni-16Cr-16Mo-4W alloy shows better resistance to environmental fatigue than the Ni-28Mo alloy. This difference is discussed in terms of the electrochemical passive/active behavior of both alloys. Plasma coating of carbon steel specimens with Ni-16Cr-16Mo-4W powders improves their resistance to corrosion fatigue in 4% NaCl solution.