WC/Co/Cr thickness

[sprayloud]

A quick question: to my knowledge HVOF or HVAF sprayed WC/Co coating can be up to 0.2-0.3mm thick without risk of cracking etc. I've came across some information about HVOF/HVAF coated WC/Co/Cr coating 1mm thick. Is this possible ? With what equipment ?

[Vadim Verlotski]

(03-12-2018 02:32 PM)sprayloud Wrote:  A quick question: to my knowledge HVOF or HVAF sprayed WC/Co coating can be up to 0.2-0.3mm thick without risk of cracking etc. I've came across some information about HVOF/HVAF coated WC/Co/Cr coating 1mm thick. Is this possible ? With what equipment ?

It is possible. We also applied over 2 mm WC-Co-Cr with CJS-burner. Problem with the thick layers is that you have to work with very thin individual layers (about 1 micron per pass) and take care of temperature (component may not be over 120°C). If you coat "normal" with approx. 10 micron per pass, the stresses in the layer rise too fast with the increasing layer thickness and you can not get over 0.5 mm without cracks. Whether HVOF or HVAF is used, plays a minor role, the main thing - do not choose too hot parameters. It is said that HVAF has advantages in the large layer thicknesses, but HVOF with "fast and cold" parameters does it just as well.

[Vig]

Yes, it is possible.
We sprayed 3 mm with HVAF several times. Andrew Verstak from Kermetico sprayed 12 millimeters of 86/104 onto a rotating part for a customer with his AK7.
With HVAF you need much less effort to spray WCCoCr than with HVOF. Even a mediocre operator can make a 1 mm thick coating.
Regards,
Vig.

[Arturas]

Hi,
Yes it is possible , but it depends on shape and geometric parameters of the component you spray on. Write more clear .
Also spraying parameters but Vadim wrote about that!!
What equipment do you have?

(03-12-2018 02:32 PM)sprayloud Wrote:  A quick question: to my knowledge HVOF or HVAF sprayed WC/Co coating can be up to 0.2-0.3mm thick without risk of cracking etc. I've came across some information about HVOF/HVAF coated WC/Co/Cr coating 1mm thick. Is this possible ? With what equipment ?