Erosion–Corrosion Behavior of 90/10 and 70/30 Copper–Nickel Tubes in 1 wt% NaCl Solution

Abstract

The erosion–corrosion behavior of 90/10 and 70/30 copper–nickel tubes was investigated by in situ electrochemical tests on a self-built loop apparatus and ex situ surface characterization. The corrosion product film that formed at 1.5 m/s for the 90/10 tube and at 0.5 m/s for the 70/30 tube showed the best corrosion resistance. For the 90/10 tube, a continuous film existed below 3 m/s and mainly inhibited a cathodic reaction. For the 70/30 tube, a continuous film existed in the range of 0.5–4.7 m/s and was more similar to typical passive film electrochemically, although it was cracked at 4–4.7 m/s. So, the “critical flow velocity” of the 90/10 tube was between 3 m/s and 4 m/s, and that of the 70/30 tube was beyond 4.7 m/s.

Microstructure, Mechanical and Corrosion Properties of Copper-Nickel 90/10 Alloy Produced by CMT-WAAM Method

“…Based on the data obtained regarding the corrosion rate, the analyzed material can be classified based on the literature data [ 34 ] as low corrosion (below 0.025 mm/year) whereby the material is practically non-corrosive or the corrosion is very slow. Most works in the literature focused on the study of the corrosion properties of Cu-Ni 90/10 alloys [ 22 , 23 , 26 , 27 , 31 , 32 ] presenting electrochemical measurements carried out in the environment of a NaCl solution with a concentration of 1 to 3.5% or seawater solutions with additional chemical components [ 21 , 24 , 25 , 28 ]; therefore, it is difficult to directly compare the obtained results.…”

“…Based on the data obtained regarding the corrosion rate, the analyzed material can be classified based on the literature data [34] as low corrosion (below 0.025 mm/year) whereby the material is practically non-corrosive or the corrosion is very slow. Most works in the literature focused on the study of the corrosion properties of Cu-Ni 90/10 alloys [22,23,26,27,31,32] presenting electrochemical measurements carried out in the environment of a NaCl solution with a concentration of 1 to 3.5% or seawater solutions with additional chemical components [21,24,25,28]; therefore, it is difficult to directly compare the obtained results. The authors of work [18] for a standard CuNi10Fe1.8Mn alloy obtained an ultimate tensile strength of 235 MPa and a hardness of 86 HV (lower properties than the tested printed samples by about 52%) after the continuous casting process while high mechanical properties were obtained only after the cold working process with a degree of relative strain of 94%.…”

“…Cu-Ni 90/10 alloys produced by conventional production techniques in the casting and plastic forming process have been the subject of many studies of mechanical properties [ 18 , 19 , 20 ] and corrosion properties in the conditions of seawater and other solutions [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. The microstructure and properties of the friction-welded CuNi10 alloy were also investigated [ 29 ].…”

Microstructures and Corrosion Properties of Wire Arc Additive Manufactured Copper–Nickel Alloys

“…Additionally, its protection of the matrix is not as desirable when compared with that of stainless steels [28]. The cuprous oxide (Cu 2 O) film produced is believed to be predominately responsible for the corrosion protection, and the thicker passive film mainly reduces the corrosion rate by inhibiting the cathodic processes, such as the oxygen reduction reaction on the sample surface [29]. In this work, the passive film formed during polarization test and that generated at OCP during the EIS test are formed within hours and may not be thick enough to inhibit the cathodic reaction by mitigating oxygen migration.…”

Modeling of the corrosion behavior of B30 alloy in a deep‐sea environment by using the response surface methodology

“…According to the field statistics data, the marine equipment suffers from a series of severe problems such as corrosion or even fracture in early stages of the working life. [ 4–8 ] To prolong this service time, investigation of the corrosion behavior of marine materials in the deep‐sea environment is crucial.…”