Extending the Lifetime of Oil and Gas Equipment with Corrosion and Erosion-Resistant Ni-B-Nanodiamond Metal-Matrix-Nanocomposite Coatings

摘要

The increasing pressure to eliminate hard chromium in oil and gas applications because of environmentalrnconcerns related to hexavalent chromium has fueled the need for substitutes with comparable economicsrnand performance. Nickel (Ni) presents a viable alternative coating material, which is widely used inrnindustrial applications over the past five decades because of its unique characteristics in improvingrnresistance to corrosion, abrasion and wear. Performance of Ni-based coatings can be further improvedrnwith the development of metal-matrix-nanocomposite coatings (MMnC). This paper presents the developmentrnof a new class of MMnCs prepared by electrolytic deposition. The nanocomposite coatings arernformed by the simultaneous impingement of the nanoparticles onto the growth surface and the envelopmentrnof said particles by the depositing Ni ions. In this new process, the metal matrix comprises Ni-Brncompositions produced with a nontraditional Boron (B) source, which enables higher B-contents in thernmatrix, resulting in superior hardness and resistance to corrosion.rnIncorporation of diamond nanoparticles into the matrix improves resistance to wear without negativelyrnaffecting the corrosion resistance. Dispersed nanodiamond decreases the grain size of Ni-B matrix andrnimproves the mechanical properties of the coatings. Ultimately, size, nature and content of particlesrndispersed in the matrix determine the properties of the coatings. This paper describes the impact thatrnBoron and nanodiamond incorporated in the matrix have on the growth, microstructure, corrosion andrnmechanical properties of the new class of metal-matrix nanocomposite coatings. Experimental results alsornshow that this material outperforms current commercially available electroless Ni-B coatings. The novelrncoatings presented extend the lifetime of equipment used in corrosive and erosive environments in thernexploration and production of oil and gas.