Page 117 - QRedition5.0 062021

Quality Requirements Edition 5.0 European Enamel Association

Testing report 8.6.3 Testing of adherence of porcelain and vitreous enamel to steel
In the testing report, the following has to be mentioned: of more than 3 mm thickness
kind and origin of the test plates

place and date of testing Purpose and scope

resistance class, according to EN ISO 28706-4 (classes AA-unclassified) The test method described in this specification sheet is to classify the adherence of enamel
testing-time and -temperature to steel on enamelled articles made of steel heavier than 3 mm of thickness.

Test method

The enamelling of the test piece is to destroy by impact. The destruction can be executed
by a dynamic ball-indentation or a blow of a hammer. Because of the chipping and splintering
enamel safety glasses are absolutely to be worn during this test.

Test device
No binding regulation

Judgement of the test-spot

Following the destruction by only one single impact, relics of enamel on the steel surface
must be clearly visible. The steel surface may not appear silvery bright. Because of the un-
defined mechanical shock method, a classification into ranks of adherence is not possible.
One virtually has to decide between ”good” or ” insufficient”.

Test report
To be mentioned in the test report:
kind and origin of the test piece
place and date of testing
location of the test-spot on the test piece
judgement of adhesion

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