Role of micro-factors on microstructure and on the tribological performance of HVOF coatings: A review

Abstract

Mechanical components, whether stationary or moving are subjected to wear and corrosion. A combined effect of these two is even more deleterious. Thermal spray technique proves to be an effective solution to address these issues. HVOF coatings owing to their inherent characteristics like high hardness, adhesion, density (porosity <1%) its provide enhanced mechanical and tribological performance and so are widely used across industries. Micro-factors like presence of pores, oxides and cracks, matrix and binder properties, addition of Cr, cohesive strength and boundary regions etc. do influence the coating behaviour, besides the deposition parameters. The objective of this paper is to review the effect of above mentioned factors on the wear and corrosive performance of the coatings for industrial and research viewpoint.

Slurry erosion behavior of thermally sprayed ceramic nanocomposite coatings on turbine steel

“…This increase in the erosion rate with increase in impact velocity was mainly due to the increase in kinetic energy of striking particles. Similar results are reported by many authors 45–47 …”

“…Similar results are reported by many authors. [45][46][47] The ANOVA of the experimental results exhibited that the velocity and slurry concentration were the most significant parameters in all test runs, influencing the erosion rate of these coatings. These results were also like the outcome of various researchers.…”

Application of Hvof Technology for Wc-Based Wear-Resistant Coatings – An Overview

“…Согласно источникам [7][8][9] установлено, что с помощью различных методов термического напыления, таких как воздушно-плазменное напыление (APS), вакуумное плазменное напыление (VPS), детонационный пистолет, дуговое напыление, пламенное напыление и высокоскоростное кислородное напыление (HVOF) наносятся в основном покрытия на основе керамико-металлического композита (керметы), в частности карбид-вольфрам-кобальт WC-Co, карбид-вольфрам-кобальт-хром WC-Co-Cr, а также хром-карбид-никель-хром Cr3C2-NiCr [10][11][12][13]. Однако процесс HVOF получил признание за свои преимущества, включая меньшую пористость, уменьшение реакций разложения, более высокую степень сохранения карбида вольфрама (WC), и лучшую адгезию между карбидом вольфрама (WC) и металлической связующей фазой [14][15][16][17][18][19][20].…”