The authoritative public forum
  for Metal Finishing since 1989
-----

Plasma spray coatings

hi to all,
WE are doing plasma spray coatings.WE make plume by using argon ,hydrogen,argon as carrier gas,tribaloy T 800 powder with voltage at 73v,500 ampere,argon 150 scfh,hydrogen 8 scfh.The problem is this that we are facing tensile failure,and porosity and voids in the metellograph.we have no knowlege at all that what factors influence plasma coatings quality.Can any one send me literature about the parameters setting techniques to improve the tensile,hardness and metellography of plasma spray process.Please help me in this regard as I am not getting any literature on the google search about the technical discussion of plasma spray that how tensile is improved,how hardness is improved and how mettelograph is improved
regards,

IFTIKHAR ALI
researcher - Pakistan
May 30, 2008

---

First of two simultaneous responses -- May 30, 2008

The maker of your thermal spray equipment should be able to help you out.
I have no idea what t800 powder is, but do know from years of certifying flame and plasma coatings that ALL of the parameters have to be maintained in tight tolerance.
It is not possible to talk about problems without seeing the actual microsections and the work setup. You may have to hire a consultant to help you out, since it sounds like you are using a copy of some other companies equipment (since you did not say what you were using)

James Watts
- Navarre, Florida

---

Second of two simultaneous responses --

You should ask the manufacturer of your equipment as each one performs different.

Guillermo Marrufo
Monterrey, NL, Mexico
June 1, 2008

---

Hello,

You really need help form an expert.
Plasma spraying needs parameters optimization.
Many parameters are involved. If you don't have knowledge then it will take time ot obtain the expected results.

Jose Castellanos

Jose Castellanos
- Minneapolis, MN, USA
June 11, 2008