Locate the failure interface

Before changing the adhesive, check whether flock released from the adhesive film, the film released from the metal, or the metal coating or oxide layer failed.

Oil, cleaning residue and loose oxide can pass an initial hand test and separate after heat exposure.

Repeat the test with controlled variables

Record cleaning, primer, film thickness, open time and drying before heat aging. Use the same flock and metal batch when comparing samples.

The test temperature and time should reflect the buyer's acceptance method. They should not be converted into a general service-temperature claim.

Failure interfaceCleaning recordOxide or coating conditionFilm thicknessHeat-aging method