Multiscale characterization of seawater pipe erosion of B10 copper–nickel alloy welded joints

Abstract

In seawater pipeline, the welding joint is a non-uniform structure composed of welding seam, base metal and heat affected zone. It has inhomogeneity in chemical composition, organizational structure, residual stress, etc. As local defects and high turbulence accelerate corrosion, the welding joint is often the weakest link in pipeline corrosion. Herein, the electrochemical corrosion behavior of B10 alloy welded joint in flowing seawater is studied from macroscopic and submicroscopic viewpoints using AC impedance, linear polarization, array electrode and morphological characterization. The results reveal that the corrosion rate of weld metal (WM), base metal (BM) and heat-affected zone (HAZ) decreased with the increase of time. Combined with SEM and EDS analysis, it can be seen that the increase in time led to the decomposition and accumulation of corrosion products, which gradually enhanced the corrosion resistance of welded joints. At the submicroscopic scale, WM acts as a cathode to mitigate corrosion during the later stages of high flow rate.

Development of a Novel Water Jet Polisher Using Soft Abrasives for Small Complex-Structure Heat Pipes of Aluminum Alloy Produced Using Additive Manufacturing

“…However, it is obvious that when the fluid carrying solid particles flows through the bend, it will inevitably cause erosion on the wall, especially in the area where the flow field distribution is concentrated, and the effects of this erosion are also magnified by the wear particles traditionally used [23][24][25][26][27][28]. Therefore, there is an urgent need to develop new non-erosive or weak erosion abrasives in this application field.…”

Characterization of Corrosion Behavior of TA2 Titanium Alloy Welded Joints in Seawater Environment

“…In order to better develop and utilize the ocean, marine facilities are particularly important. As an important part of marine facilities, seawater piping system is faced with very bad environment (Cheng et al, 2017;Zhang et al, 2022), so the requirements for engineering materials are very high (Thiruvengadam and Conn, 1972;Wang, 2016). Titanium alloy has been widely used in the construction of offshore facilities because of its good corrosion resistance and high mechanical properties (Mochizuki et al, 2007;Yang et al, 2011;Pang and Blackwood, 2015;Rondelli and Vicentini, 2015).…”