The microstructural dependence of wear and indentation behaviour of some plasma-sprayed alumina coatings

Mechanical behavior of Ti cold spray coatings determined by a multi-scale indentation method

“…Reduction in grain size or increase in material work hardening and dislocation density are often associated with the increase in the hardness [13]. On the other hand, a decrease in the hardness can be tied to material defects such as porosity and in the case of coatings to the particle de-bonding [13,29,38]. The degree to which these parameters affect the hardness measurements depends on the indentation load and size.…”

Microstructural and Tribological Investigation of High-Velocity Suspension Flame Sprayed (HVSFS) Al2O3 Coatings

“…Particularly, this paper will deal with Al 2 O 3 , one of the ceramic materials most commonly employed in the thermal spray industry. It has a relatively low cost, it possesses high hardness and chemical stability, making it suitable for various wear-resistant applications also in corrosive environments, and it is an excellent electrical insulator, making it a frequent choice for dielectric layers and supports for sensors, heating elements, etc… (Ref 20 [24][25][26][27], and the high thickness of the coating can, in various instances, be undesirable: for example, it is undesirable in some mechanical components, when strict dimensional and geometrical tolerances are required, or in electrical/ electronic equipment, when devices to be heated must not offer excessively high thermal insulation. Thus, improvements can be expected by the use of the HVSFS spraying technique, enabling the deposition of thinner coatings with better cohesion between submicron-sized lamellae, and lower porosity with much smaller pores.…”

Erosion Behavior of Plasma Sprayed Alumina and Calcia-Stabilized Zirconia Coatings on Cast Iron Substrate

“…Linkage of these pre-existing cracks with indentation cracks could have aided the material removal process. The thermal cracks normal to the surface, the interfaces between adjacent layers of splats can be identified as structural weakness for both Al 2 O 3 and ZrO 2 5CaO coatings, as described in [33,34]. The erosion of plasma sprayed coating of lamellar structure occurs through spalling of surface lamella resulting from impact of abrasives.…”