Corrosion or Contamination on JP8000

[xxxxmgulkokan]

Dear All;

We are using Praxair JP8000 system and it works with oxygen and kerosene and powder is 1350VM(%86WC-%10C-%4CR). 

We have started to see big black point. This points are close the upper side of the coating.  

This points will be porosity or contamination but we couldn't be sure that which one is. I uploaded 2 pictures. Please see below links.

Our thickness is 0.005 inches. 

Could you please give the information how we can fix this issues ?

https://ibb.co/HFSw3d0

https://ibb.co/Dp2xmzj

[Vadim Verlotski]

It looks like a problem with overspray: the low-energy particles from the periphery of the flame stick to the surface and form porous structures. During the next pass of the burner these structures are not removed and remain inside the layer.
In order to remove these weakly bound particles, you need a compressed air jet that is strong enough. It is usually sufficient if the nozzles of the cooling installed on the torch are moved closer to the coating spot.

[RAY SENFENG]

For laser claddings please contact ray@sfcnclaser.com