Loss of adhesion at the bond line or between layers, showing as blisters, lifted areas or sections that peel away. Root causes include poor surface prep, contamination, insufficient profile, high residual stress from thick or hot-sprayed layers, dusting between passes and thermal mismatch. It is checked by tapping, bend tests on coupons, visual and dye-penetrant inspection and cross sections.
Coating's ringing hollow when you tap it, there's delamination under there, strip it.
A coin or small tap hammer finds a lot of it: a dull, hollow sound over a coated area is worth a closer look.
Also heard as
- disbonding
- debonding
- peeling
Related terms
Lifting
Shop word for coating peeling up at an edge, often after tape removal, grinding or machining.
Spalling
Flakes or chunks of coating breaking away from the surface, typically under thermal cycling or impact.
Adhesive failure
A bond test break at the coating-substrate interface, meaning the coating let go of the base metal.
Residual stress
Stress locked into a coating and substrate after spraying, from splat shrinkage, cooling and impact.
Same word, different worlds
Separation between layers of a board's laminate or between laminate and copper, usually from heat or moisture.
Concrete & CementA surface layer that has split away from the concrete below it, found by the hollow sound it makes when tapped.
NonwovensSeparation of the layers of a laminate or multilayer nonwoven, such as an SMS or a film composite.