TBC
06-02-2015, 06:12 PM,
#1
TBC
Hello to everybody,

I have a problem.
I deposited on nemonic 60 support Amdry 997 by HVAF thickness 0,1 mm and ZrO2/Y2O3 (92/8) by APS with F4 gun, thickness 0,25 mm.
I have tested the samples in an electric furnace at 1200ºC for 24 hours, followed by cooling at 25ºC in 50 min.
After 3 cycles there appeared spalling between bond coat and top coat.
Does anybody know if there is a treatment necessary before testing the samples ?
Can anybody indicate me the deposition parameters for Metco 222A with F4 gun ?

Thanks !

Ion
Reply
06-03-2015, 05:57 AM, (This post was last modified: 06-03-2015, 06:00 AM by Vadim Verlotski.)
#2
RE: TBC
(06-02-2015, 06:12 PM)plasmajet1990 Wrote: Hello to everybody,

I have a problem.
I deposited on nemonic 60 support Amdry 997 by HVAF thickness 0,1 mm and ZrO2/Y2O3 (92/8) by APS with F4 gun, thickness 0,25 mm.
I have tested the samples in an electric furnace at 1200ºC for 24 hours, followed by cooling at 25ºC in 50 min.
After 3 cycles there appeared spalling between bond coat and top coat.
Does anybody know if there is a treatment necessary before testing the samples ?
Can anybody indicate me the deposition parameters for Metco 222A with F4 gun ?

Thanks !

Ion

Hi plasmajet1990,

Maximum permissible application temperature for Amry 997 (NiCoCrAl [Ta, Hf, Si] Y) is 1050°C (long term < 1000°C). It's no wonder that bondcoat was so heavily oxidized after 24 hours at 1200°C, that topcoat flaked off.


Attached Files
.pdf   DSMTS-0093.4_NiCoCrAlY.pdf (Size: 197.41 KB / Downloads: 1,186)
Reply
06-03-2015, 09:52 AM,
#3
RE: TBC
(06-03-2015, 05:57 AM)Vadim Verlotski Wrote:
(06-02-2015, 06:12 PM)plasmajet1990 Wrote: Hello to everybody,

I have a problem.
I deposited on nemonic 60 support Amdry 997 by HVAF thickness 0,1 mm and ZrO2/Y2O3 (92/8) by APS with F4 gun, thickness 0,25 mm.
I have tested the samples in an electric furnace at 1200ºC for 24 hours, followed by cooling at 25ºC in 50 min.
After 3 cycles there appeared spalling between bond coat and top coat.
Does anybody know if there is a treatment necessary before testing the samples ?
Can anybody indicate me the deposition parameters for Metco 222A with F4 gun ?

Thanks !

Ion

Hi plasmajet1990,

Maximum permissible application temperature for Amry 997 (NiCoCrAl [Ta, Hf, Si] Y) is 1050°C (long term < 1000°C). It's no wonder that bondcoat was so heavily oxidized after 24 hours at 1200°C, that topcoat flaked off.

Yes, I know, but it has to resist
Thanks!
Reply
06-04-2015, 08:04 AM,
#4
RE: TBC

Yes, I know, but it has to resist
Thanks!

[/quote]

It has to resist 1200°C at YSZ-surface, but on interface bond coat - top coat the temperature should not exceed 950°C. To create these conditions (temperature gradient 200-250°C) is necessary to heating the sample by the coated surface and cooling by the substrate.
Reply
06-04-2015, 06:46 PM,
#5
RE: TBC
(06-04-2015, 08:04 AM)Vadim Verlotski Wrote: Yes, I know, but it has to resist
Thanks!

It has to resist 1200°C at YSZ-surface, but on interface bond coat - top coat the temperature should not exceed 950°C. To create these conditions (temperature gradient 200-250°C) is necessary to heating the sample by the coated surface and cooling by the substrate.
[/quote]

Dear Vadim,

Yes, the temperature gradient is 170ºC for 0,25 mm top coat, if the test is made in the flame furnace with cooled substrate :
https://www.youtube.com/edit?o=U&video_id=xVVrH89eOug

In the electric furnace the substrate is not cooled. The temperature of the substrate + bond coat is 1200ºC.

Thanks !
Ion



Reply




Users browsing this thread: 1 Guest(s)





Surface Engineering Forum Sponsor - Alphatek Hyperformance Coatings Ltd