Experimental investigation and parameter optimization of Cr2O3 atmospheric plasma spray nanocoatings

Abstract

In this research, Cr2O3 ceramic nano-sized powder particles were prepared using ball milling and then were granulated to reach the proper size for spraying. Afterward, Cr2O3 nano-coatings were deposited by atmospheric plasma spraying (APS) process onto stainless steel substrates. To optimize APS parameters, spraying was carried out under six conditions with different parameters. Microstructures of the elemental/milled powder and coatings were characterized via a field emission scanning electron microscope (FESEM) equipped with energy-dispersive spectroscopy (EDS). In this research, Cr2O3 coatings were deposited under different spraying conditions to understand the effect of APS parameters on the splat formation, deposition efficiency, and porosities of the coatings. After parameter optimization, spraying was performed under a high deposition efficiency of 46.0±1.3%. The optimized Cr2O3 coatings showed porosity content, Knoop microhardness, and adhesive strengths of 8.7±2.2%, 823±27 HK0.2, and 49±4 MPa, respectively; making them a good candidate for industrial use.

The Effect of Heat Treatment on the Microstructure and Phase Composition of Plasma Sprayed Al2O3 and Al2O3-TiO2 Coatings for Applications in Biomass Firing Plants

“…Thermal plasma jets are characterized by high velocities (100-2500 m/s) and high temperatures (2000-14,000 K). Thus, it gives the ability to spray a wide variety of materials from metals to ceramics [1][2][3][4][5][6][7][8][9][10]. Moreover, almost any ceramics or their composites with high melting points can be melted and deposited due to the high temperature of the plasma flame [2,3,10].…”

“…Thus, it gives the ability to spray a wide variety of materials from metals to ceramics [1][2][3][4][5][6][7][8][9][10]. Moreover, almost any ceramics or their composites with high melting points can be melted and deposited due to the high temperature of the plasma flame [2,3,10]. In addition, the plasma jet temperature is easily managed by adjusting the torch power, gas flow rate, or type of gas and at the same time controlling the properties of the deposited coatings [1][2][3][4][5][6][7][8][9][10].…”

“…Coatings 2021, 11, x FOR PEER REVIEW 2 of 18 addition, the plasma jet temperature is easily managed by adjusting the torch power, gas flow rate, or type of gas and at the same time controlling the properties of the deposited coatings [1][2][3][4][5][6][7][8][9][10].. Plasma sprayed ceramic coatings have many excellent properties, such as wear and corrosion resistance and high-temperature resistance.…”