Fig. 15 Schematic of coating delamination process for cermet and ceramic coatings More

Fig. 16 Coating features of the vane along the airfoil section. (a) Convex side showing intact coating and shrinkage porosity; (b) Coating-matrix interface along convex side; (c) Vane coating and coating-matrix interface along concave side. More

Fig. 17 Coating degeneration and corrosion attack in MAR-M302 vane along the concave airfoil side. (a) Fine cracking; (b) Subsurface shrinkage porosity; (c) Corrosion product penetration in the subsurface porosity. More

Fig. 18 EDX analysis of the coating and corroded area of MAR-M302 vane. (a) Al and S peaks observed in the coating; (b) Corroded fracture region showing Na, S, Al and Si peaks. More

Fig. 1 Uncoated and aluminide-coated IN-713 turbine blades that failed by hot corrosion in a marine environment. (a) An uncoated blade showing splitting along the leading edge and swelling on the surface of the airfoil. 2.7x. (b) Section taken through the leading edge of an uncoated blade More

Fig. 2 (a) A magnetite coating on hot rolled sheet, with fresh rust breaking through; (b) Hot rolled surface, about 60% covered with fresh rust; (c) Hot rolled steel, with all the original magnetite lost. Rust is beginning to darken where arrowed, to form hematite. More

Fig. 6 Plasma-spray-coated babbit microstructure. (a) Optical micrograph. (b) Scanning electron micrograph of α phase More

Fig. 12 Cage section showing general microstructure and silver coating More

Fig. 6 Trailing edge yielding and aluminide coating wrinkling associated with stress-rupture cracking on turbine airfoils More

Fig. 5 A micrograph of the fracture surface (gold coated) of Fig. 4 revealing multiple crack origins, a smooth morphology, and arrest marks More

Fig. 6 Cross-section showing electroless nickel coating delamination and cracking More

Fig. 4 XRD patterns of bond coat before and after spallation More

Fig. 6 Chromium-nickel coating layer on the marriage bolt surface. 1000× More

Fig. 7 Coating layer deteriorated by corrosion. 500× More

Fig. 48 Artifacts generated by improper platinum sputter coating of a 4.6 mm (0.18 in.) diameter polycarbonate rotating beam fatigue specimen. This SEM view shows a pattern in the coating reminiscent of “mud-cracking.” More

Fig. 12 Adhesive delamination in thermally sprayed Al 2 O 3 coating More

Fig. 13 Cohesive delamination in thermally sprayed WC-Co coating (backscattered electron image) More

Fig. 16 Bulk deformation failure of WC-Co coating, indicating cracks in the middle of the wear track and substrate migration at the edge of the wear track More

Fig. 18 Spalling of thermally sprayed WC-Co coating More

Fig. 20 Influence of normalized coating thickness on the performance of HVOF coating on 440C steel substrate (σ = 1840 MPa, or 267 ksi) More