Assessing The Results (Destructive Testing) - Elcometer 506 Guia Del Usuario

7 ASSESSING THE RESULTS (DESTRUCTIVE TESTING)

Once pulled from the surface, examine the bottom of the dolly to
assess the results.
a) Successful Test: In most cases the coating will fully adhere to the
dolly and the test can be claimed as 100% valid.
b) Partial Failure: In some cases, the coating will cover only part of
the dolly face. A partial adhesion / coating failure should be
recorded if the coating covers more than 50% of the dolly face.
Cohesive Failure: When the coating fails in the body of the
coating layer leaving some coating on the surface and some
coating on the dolly face.
c) Adhesive Failure: If no coating is present on the dolly this must be
recorded as a failure of the adhesive (or glue). This is normally
due to incorrect or insufficient mixing of the component parts of
the adhesive, incompatibility of the adhesive and the coating or
the dolly and / or test surface has not been properly prepared
before test - see Section 3 "Securing the Dolly" on page en-3.
a)
When testing coatings on concrete it is common for the adhesive bond
between the coating and the concrete to exceed the strength of the
concrete itself. In this case concrete will be removed from the surface
and will be seen on the coating on the dolly face.
Observing the test area will give additional information about the type
of failure; adhesion and cohesion between different layers of the
coating.
Adhesive
Failure
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b)
Partial Coating
Failure
c)
Coating
Failure
R
Concrete
Failure
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