MWCNTS-YSZ coating deposited by plasma thermal spray on INCONEL 738 low carbon substrate

Abstract

The surface of Inconel 738 LC samples has been coated with carbon nanotube and yttria stabilized zirconia utilizing the plasma thermal spray method. Various percentages of carbon nanotubes and yttria stabilized zirconia were utilized in the coating (100 percent nano YSZ, 96 percent nano YSZ +4 percent CNTs, 94 percent nano YSZ +6 percent CNTs, and 92 percent nano YSZ +8 percent CNTs). After coating, a cyclic hot corrosion testing has been conducted, followed by SEM and XRD on all samples. SEM cross-section micrographs were utilized to quantify coating thickness. After 50 hrs of corrosion in 67 percent wt. V2O5 +33 percent wt. Na2SO4 at 950 degree centigrade, the changing weight of absence and coated specimens was measured. The cumulative weight change per surface area of coated specimens at temperatures of 950 °C was found to be 0.0095, 0.0075, 0.006, and 0.0057 mg.cm–2, (E,F,G,H) respectively. The best coating to resist hot corrosion was showed by specimens coated with 92% wt. yttria +8%wt. carbon nanotube. There are no oxides in the base specimens, according to X-rays of coated samples. Images of scanning electron microscopy for the surface layer revealed that it has a significant porosity and that some of the layer of coating s had microcracks.