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Thickness measurement: ceramics coatings on cast iron

1998

Hello,

I'm looking for system to measure thickness of thermally sprayed ceramics coatings on cast iron. Substrate parts are relative large and all kinds of destructive methods are out of question.

Does the thickness of the substrate have any effect how much ceramics will accumulate during spraying e.g. due different kind of heat history? Can the coupons for cross section analysis be over ten times thinner than actual sprayed parts? for example 6mm/120mm

kind regards,

Erno simonen
Finland

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1998

if you are spraying ceramics, you are using plasma or better equipment.

Magnetic measuring equipment is quite accurate on most ceramics over cast. The magnetic permeability of the cast is different than the steel coupon as well as the thickness and edge effect can cause errors in magnetic readings. Properly operated, they are quite accurate over non magnetic ceramics.

Many operators will not spray the coupon exactly the same as the part and that is probably a significant source of error also.

The temperature of the part affects metallurgy and adhesion, but not thickness of deposition to any extent that I am aware of.

James Watts
- Navarre, Florida

Dear reader. I am intrested in measuring the thickness and thickness distribution of electroformed nickel foil (50 x 50 cm). The thickness is approximately 50 microns. I have to measure the thickness distribution within a statistical error of 0.05 microns. What type of measurement system is recommended and where can I buy it? Regards...

Alfred J. Horstik
Storkgroup the Netherlands
1999

I suggest that 'Galvano' tester could be a good sol for thickness accuracy

CHEN YING YING
Metal Coating Malaysia - Johor, Malaysia
2007