Effect of YSZ and SiC Reinforcements on the Mechanical Properties of Cr2O3 Plasma-sprayed Nanocoatings

In this research, Cr2O3, YSZ, and SiC ceramic nanopowders were prepared, mixed and then agglomerated to reach the proper size for spraying. Afterward, Cr2O3 (C), Cr2O3-20YSZ (CZ), and Cr2O3-20YSZ-10SiC (CZS) nanocoatings were deposited onto 304L steel substrates using Atmospheric Plasma Spraying (APS) process. Microstructures of the initial/milled powders and the coatings were characterized using Field Emission Scanning Electron Microscope (FESEM) equipped with EDS. X-ray diffraction (XRD) analysis showed only the peaks of the initial powders without any traces of impurities and new-appearance peaks. Considering mechanical properties evaluations, producing CZ coating through adding tough YSZ particles to C coating caused a considerable increase in the coating toughness while decreased its hardness. Subsequent addition of intrinsically hard SiC particles to the CZ composite coating increased the degraded hardness of the coating to a higher value. However, Composite CZ and CZS coatings showed lower bonding strengths and higher porosities when compared to C coating.

Keywords:

Cr2O3-YSZ-SiC , Ceramic Matrix Nanocomposite , Plasma-sprayed Coating , Ball Milling , Mechanical Properties.