metco 101bns powder / tensile strength

[RogerMilam]

has anyone used metco 450ns{bond] and metco 101bns top in your applications? i have been spraying this for years and average tensile with glue is 8100, and 3500 with f100 wafers, i would like to know what any of you all average.

thank you, Roger Milam

[Boris Volfman]

has anyone used metco 450ns{bond] and metco 101bns top in your applications? i have been spraying this for years and average tensile with glue is 8100, and 3500 with f100 wafers, i would like to know what any of you all average.

thank you, Roger Milam

Hello,
Liquid glue penetrates within porosive coating and increases it's strength.
Actually, you check the strength of coating filled by glue.
Correct values gives wafers of FM1000 (I think, this is correct name).
FM1000, not liquid glue is actually approved for the most of aerospace applications.
For this coatings combination we get strength of about 3000-5000 MPa/
Regards,
Boris

[RogerMilam]

has anyone used metco 450ns{bond] and metco 101bns top in your applications? i have been spraying this for years and average tensile with glue is 8100, and 3500 with f100 wafers, i would like to know what any of you all average.

thank you, Roger Milam

Hello,
Liquid glue penetrates within porosive coating and increases it's strength.
Actually, you check the strength of coating filled by glue.
Correct values gives wafers of FM1000 (I think, this is correct name).
FM1000, not liquid glue is actually approved for the most of aerospace applications.
For this coatings combination we get strength of about 3000-5000 MPa/
Regards,
Boris

Thanks Boris,

that is what i am seeing often, Pratt is the only one that is asking for 5000 psi min, and we are bouncing above and below that number.

[pgilson]

Hi Guys,

Someone can tell me why the bond strenght between metco 450ns & 101bsn is it so variable ?
Currently with F4 gun, we are not able to meet the 5000psi asked by spec on theses powders. We are only able to only reach 4000psi.
In the past, the average results was more than 6000psi but this month, it isn't possible.
The faillure is always situeted at the interface bond coat - top coat.
I have made on test of 101bsn on metco 443ns, and now the faillure is at 4800 psi 100% in the 101bns.

Can you helps me ?
Many thanks,
Paul Gilson

[Vadim Verlotski]

Hi Guys,

Someone can tell me why the bond strenght between metco 450ns & 101bsn is it so variable ?
Currently with F4 gun, we are not able to meet the 5000psi asked by spec on theses powders. We are only able to only reach 4000psi.
In the past, the average results was more than 6000psi but this month, it isn't possible.
The faillure is always situeted at the interface bond coat - top coat.
I have made on test of 101bsn on metco 443ns, and now the faillure is at 4800 psi 100% in the 101bns.

Can you helps me ?
Many thanks,
Paul Gilson

Hi Paul,

There is nothing surprising in the fact that the adhesion strength of the ceramic coating with the nickel-aluminum sublayer varies widely. A wide range of mechanical properties (large Weibull modulus) is characteristic not only of coatings, but also of compact ceramic materials. This is explained by the absence of plastic deformation in ceramic materials and their high fragility. The situation with coatings is even worse than with compact ceramics, since ceramic coatings have pores, microcracks, and internal stresses. In addition, the smallest changes in the deposition parameters can lead to very large changes in the properties of ceramic coatings.
In other words, there are many possible reasons why the bond strength of your coating to the subcoat has changed and it is impossible to name a specific reason without a detailed comparison of all coating conditions.

[pgilson]

Hi Guys,

Someone can tell me why the bond strenght between metco 450ns & 101bsn is it so variable ?
Currently with F4 gun, we are not able to meet the 5000psi asked by spec on theses powders. We are only able to only reach 4000psi.
In the past, the average results was more than 6000psi but this month, it isn't possible.
The faillure is always situeted at the interface bond coat - top coat.
I have made on test of 101bsn on metco 443ns, and now the faillure is at 4800 psi 100% in the 101bns.

Can you helps me ?
Many thanks,
Paul Gilson

Hi Paul,

There is nothing surprising in the fact that the adhesion strength of the ceramic coating with the nickel-aluminum sublayer varies widely. A wide range of mechanical properties (large Weibull modulus) is characteristic not only of coatings, but also of compact ceramic materials. This is explained by the absence of plastic deformation in ceramic materials and their high fragility. The situation with coatings is even worse than with compact ceramics, since ceramic coatings have pores, microcracks, and internal stresses. In addition, the smallest changes in the deposition parameters can lead to very large changes in the properties of ceramic coatings.
In other words, there are many possible reasons why the bond strength of your coating to the subcoat has changed and it is impossible to name a specific reason without a detailed comparison of all coating conditions.

Hi Vadim, 

Thanks a lot for your answer !

Currently, the only parameters that we see is the moisture in the powder and the humidity in the atmosphere of the coating department. We can usually see lower humidity (less than 30%). Now we can have more than 40% due to bad weather conditions.
For the powders, we have between 2 & 6% of humidity at 65°C.
Theses parameters are the only parameters we have seen changed since the beginning of this problem and this problem appears only on these 2 powders.
We are waiting for the next scheduled maintenance to kown more about the modified parameters of this machine.

[landemarre]

Hi Guys,

Someone can tell me why the bond strenght between metco 450ns & 101bsn is it so variable ?
Currently with F4 gun, we are not able to meet the 5000psi asked by spec on theses powders. We are only able to only reach 4000psi.
In the past, the average results was more than 6000psi but this month, it isn't possible.
The faillure is always situeted at the interface bond coat - top coat.
I have made on test of 101bsn on metco 443ns, and now the faillure is at 4800 psi 100% in the 101bns.

Can you helps me ?
Many thanks,
Paul Gilson

Hi Paul,

There is nothing surprising in the fact that the adhesion strength of the ceramic coating with the nickel-aluminum sublayer varies widely. A wide range of mechanical properties (large Weibull modulus) is characteristic not only of coatings, but also of compact ceramic materials. This is explained by the absence of plastic deformation in ceramic materials and their high fragility. The situation with coatings is even worse than with compact ceramics, since ceramic coatings have pores, microcracks, and internal stresses. In addition, the smallest changes in the deposition parameters can lead to very large changes in the properties of ceramic coatings.
In other words, there are many possible reasons why the bond strength of your coating to the subcoat has changed and it is impossible to name a specific reason without a detailed comparison of all coating conditions.

Hi Vadim, 

Thanks a lot for your answer !

Currently, the only parameters that we see is the moisture in the powder and the humidity in the atmosphere of the coating department. We can usually see lower humidity (less than 30%). Now we can have more than 40% due to bad weather conditions.
For the powders, we have between 2 & 6% of humidity at 65°C.
Theses parameters are the only parameters we have seen changed since the beginning of this problem and this problem appears only on these 2 powders.
We are waiting for the next scheduled maintenance to kown more about the modified parameters of this machine.

Hello
5000 PSI is high for 101BNS, in aviation maximum request is around 3600 PSI, this is already high value I think (it depend of thickness value are for around 200 micrometers).
We have noticed tensile change for around 6 month, we have far higher values than ever, and this change match with production area in US and my point of view new batch are better produced than in past. Try change powder batch, perhaps there is a link.