ASTM B571
Standard Practice for Qualitative Adhesion Testing of Metallic Coatings
Provides qualitative methods for evaluating adhesion of metallic coatings to their substrates.
What ASTM B571 specifies
ASTM B571 collects qualitative adhesion tests for metallic and inorganic coatings. Available methods include bend, burnish, chisel or knife, file, grind-saw, heat-quench, impact, peel, push, scribe-grid, and thermal-shock approaches. Not every method suits every coating-substrate combination, geometry, or thickness. Most methods are destructive and indicate gross adhesion failure rather than producing a universal numerical bond strength. The governing coating specification or purchase order should select the method, specimen location, preparation, and acceptance criterion. Passing one B571 method does not imply that the coating will pass every other method.
ASTM B571 types and classes
Every designation the document defines, with the thickness it requires and the tests it imposes.
| Designation | Meaning | Requirement / test |
|---|---|---|
Bend | Bends the specimen to strain the coating-substrate interface | No unacceptable peeling, flaking, or separation |
Burnish | Rub or burnish test intended to reveal poor adhesion | No lifting or blistering under the specified action |
Chisel, file, grind-saw, or peel | Exposes or loads a coating edge to reveal interfacial separation | No separation beyond the permitted damage zone |
Heat-quench or thermal shock | Uses differential thermal strain to challenge adhesion | No blistering, peeling, or flaking |
Scribe-grid | Cuts a grid through the coating and examines edge lifting | Acceptance as specified by the governing document |
Tests and the drawing call-out
Tests the document imposes
- Bend
- Burnish
- Chisel or knife
- File
- Grind-saw
- Heat-quench
- Impact
- Peel
- Scribe-grid
How to cite it
Drawing call-out
TEST COATING ADHESION PER ASTM B571, <METHOD>; ACCEPTANCE: <CRITERION>Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
ASTM B571 — frequently asked
Is ASTM B571 a quantitative pull-strength test?
Generally no. It provides qualitative adhesion methods that reveal peeling, flaking, blistering, or separation.
Which ASTM B571 method should be used?
Use the method required by the governing coating specification or select one compatible with the coating, substrate, thickness, and part geometry.
Are ASTM B571 tests destructive?
Most methods damage the coating or specimen and should be planned on coupons or sacrificial parts when necessary.
ASTM B571 is copyrighted by ASTM International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗