Wear and Erosion-Corrosion Behaviour of Electroless Ni-P Composite Coatings with NiTi Nanoparticle Additions

Abstract

Electroless Ni-P coatings have high hardness and corrosion resistance but low toughness. The addition of super-elastic NiTi nanoparticles have been previously developed and shown to improve the coating’s ductility. However, the coating’s wear and erosion-corrosion resistance needed to be assessed. Different thicknesses of Ni-P and Ni-P-NiTi coatings were developed on API X100 and AISI 1018 substrates and characterized using SEM, EDS, XRD, and micro-hardness. Their sliding wear resistance was tested by multiple pass wear tests. Slurry pot erosion-corrosion tests were conducted to assess their performance to potentially protect a pipeline under similar conditions. Using both the material loss rates and observable wear behaviour, the effect of coating thickness and the presence of particles was evaluated. It was found that the thickness of the coating greatly influences its durability, and its effectiveness differs depending on the wear process. The addition of NiTi nanoparticles demonstrated toughening mechanisms that resulted in less cracking.