HVOF is Ceramic Coating?

Not necessarily. It can be, or not, depending on the material introduced onto the oxy-fuel stream.

Hi,

ceramic coatings like ceramic paints like ceramic_S, metaceram etc. to minimize the rate of erosions.

So, you mean in high velocity oxy-fuel, if "ceramic_S, metaceram" are employed, then they are ceramic coating !!? And, if some non-ceramic compound are used, then they are non-ceramic? what is ceramic actually? (As i understand, a ceramic is substances formed by subsequent heating and cooling..!!)

Ceramic implies nonmetallic (at least in my dictionary).

Before asking any further uninformed questions, why not read the "High velocity oxygen fuel spraying (HVOF)" section of the link provided by AP#1?

Dear saurababu,

I repeat Tarnado's comment at #2 "Not necessarily. It can be, or not" and just to add Little bit.

How you presume that only ceramic coating can give protection from excessive pitting? Deposits by HVOF spray is different from other ceramic coatings applied by brush or hand held spray for prevention of corrosion or erosion of static or slow moving components. In HVOF oxygen and fuel at high pressure (about 150 psi) are ignited to achieve very high velocity by passing the flue gas through a nozzle. Material to be deposited is added in powder form, it can be metal, non metal or mixture of two. Even metallic deposits by HVOF can give very high wear and erosion resistance surface required for turbine. It has very high bond strength also for high velocity components.

We are using piston rods of 4inch size coated with Tungston Carbide by HVOF process. The surface hardness we get after coating is of the order of >60HRC and the wear resistance improvement is of the order that we get almost double life as compared with any other surface hardening process used for piston rods (nitrding etc.). Bonding is also very strong.