Assessing The Results - Elcometer 510 User Manual

8 ASSESSING THE RESULTS

Many National and International Standards including ISO 4624 &
ASTM D4541, require the user to record not only the pull-off force but
also the nature of the fracture by examining the bottom of the dolly
and assessing the adhesive / cohesive failure.
8.1 EXAMINING THE DOLLY
a) Cohesive Failure: The coating fails within the body of a coating
layer leaving the same coating on the surface and on the dolly
face.
b) Adhesive failure: Is a failure at the interface between layers
(intercoat) where one pulls away from the other. The "coating"
on the dolly face will not be the same as that on the test area.
en-11
R
Dolly Face
a) 100% Cohesive Failure
Dolly Face
b) 100% Adhesive Failure Between Two Layers
Substrate
Substrate
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