(05-18-2015, 06:16 AM)Giroud Wrote: Hello,
I come from Viet Nam where the thermal spray technology still new. In our workshop, we have wire arc spray (from TAFA) and HVOF system (from Castolin).
I have problem with my customer, they need WC - Niken coating sprayed by HVOF using in corrosion environment. So that, they need the porosity of surface coating is minimum and they suggest us heat treatment (fusing) after spray to decrease porosity.
We do not have the experience in this case. What is temperature for heat treatment? time, enviroment heat treatment?
So please help us if you have experience is this case.
Thanks and best regards
Hi Giroud,
Fuse undergo only a coatings of self-fluxing alloys such NiCrBSi or CoCrBSi. There are NiCrBSi alloy powders with the addition of WC, which can also to be fused. For coatings of NiCrBSi self-fluxing alloys applied usually simple flame spraying, and then melt at 1050°C. Fuse may be performed with burners or with inductor, but also in the furnace with a protective atmosphere.
If you mean HVOF-coatings of WC-Co or WC-Co-Cr, it is impossible to melt them.