I have several questions regarding the porosity of flame-sprayed ceramic coatings. I would be grateful if you could share your experience and wisdom with me.
Generally, high-temperature processes such as plasma spray are preferred over powder flame spray process for fabrication of ceramic coatings (e.g. Al2O3, Cr2O3, Fe3O4, etc.) due to their higher deposition efficiency and lower porosity level. However, it has been reported in the literature that using the consumables in the form of flexible cords and sintered rods rather than powder can generate relatively dense coatings with porosity levels (1-5 %) that are comparable to plasma-sprayed ones.
Thank you in advance for your attention.