Microstructure and Tribocorrosion Properties of Ni-Based Composite Coatings in Artificial Seawater

Bo Li,Yimin Gao,Hongjian Guo,Cong Li,Siyong Zhao,Yunchuan Kang

doi:10.3390/coatings9120822

Abstract

NiAl matrix composite coatings were prepared using atmospheric plasma spraying (APS). The mechanical and tribocorrosion properties of the NiAl matrix composite coatings, incorporated with Cr2O3 and Mo, were investigated, and the synergistic effect between corrosion and wear was studied in detail. The microhardness of the composite coating improved from 195.1 to 362.2 HV through the addition of Cr2O3 and Mo. Meanwhile, the Cr2O3 and Mo phases were distributed uniformly in the composite coatings. The X-ray diffraction (XRD) peaks of Ni-based solid solution slightly shifted to the right after adding the Mo. This was probably due to the solid solution of Mo into the matrix. The NiAl–Cr2O3–Mo composite coating had the lowest corrosion current density, wear rate and friction coefficient of 9.487 × 10−6 A/cm2, 3.63 × 10−6 mm3/Nm, and 0.18, in all composite coatings as well as showing excellent tribocorrosion properties.

Highlights

With the forward depletion of land sources, it is very hard to satisfy the development needs of industry [1,2]
Marine equipment has had an important effect on marine exploration, such as ocean wind turbines, vessels and offshore oil platforms
The NiAl and Mo powders were fabricated by gas-atomization and present the spherical shape

Summary

Introduction

With the forward depletion of land sources, it is very hard to satisfy the development needs of industry [1,2]. Ocean equipment suffers, from direct corrosion, and the onset of wear, and their combined damage greatly affects the service lives of these kinds of engineering equipment [5,6,7,8,9]. The synergism effect of wear and corrosion is very destructive and usually decided by the reciprocity of chemistry, electrochemistry, mechanics and physics [10,11]. Corrosion will influence the microstructure, hardness and roughness of worn surfaces, further affecting the wear behavior [12]. The synergetic effects of corrosion and wear reduce the service life, safety and reliability of mechanical parts in seawater environments [15]

Methods

Results

Conclusion