Hi thelai2002
to the Surface Engineering Forum.
Quote:In general, Ceramics coating is it better then Stellite coating? Or the other way round?
By ceramics do you mean oxide ceramics like chromium oxide and alumina or are you including cermet coatings like WC/CoCr and the like? Are you refering to stellite generally as metallic coating or specifically to stellite 6? and whether it is a fused/welded type or thermal spray coating?
What ever the above, your question is going to be difficult to answer. Cavitation, erosion and corrosion are complex. The fluid that is being pumped will be a big factor, clean water may result in primarily a cavition problem, while waste water could be more corrosive and erosive. Impingment angle is another, tough more ductile coatings tend to be better for ~ 90 degree, while harder coatings are best for less than 45 degree.
Popular cavitation/erosion coating are HVOF/HVAF WC/CoCr and stellite 6. Not seen any decent comparative studies between these two coating types
This recent thread and links may be worth looking at:
coating-for-caviation-t-273.html
A few more links:
(links now dead)