Adhesion is the ability for a coating such as paints and varnishes to adhere to a substrate termed as ‘substrate adhesion’ or the ability for a coating to adhere to multiple coats in the system which is termed ‘inter-coat adhesion’. For coatings to perform satisfactorily, they must adhere to the substrate on which they are applied including metal, concrete, wood, and more.
What is pull-off adhesion testing?
In accordance with ASTM D4541/D7234, ISO 4624, and others, adhesion testers evaluate the adhesion (pull-off strength) of a coating by determining the greatest tensile pull-off force that it can withstand before detaching. Breaking points, demonstrated by fractured surfaces, occur along the weakest plane within the system consisting of the dolly (loading fixture, pull stub), glue, coating layer(s), and the substrate.
The PosiTest AT series measures the force required to pull a specified test diameter of coating away from its substrate using hydraulic pressure.
Why is it necessary to test adhesion?
The goal of adhesion testing is to produce a coating failure. Coating adhesion is an indicator of how well the surface was prepared and how well the coating has bonded to the surface and/or additional coating layers. Testing adhesion offers a quantifiable method of determining if a paint or coating system is fit-for-purpose and ready to meet the quality demands of job specifications.
PosiTest® AT
Pull-off Adhesion Testers
Measures adhesion of coatings to metal, wood, concrete and other rigid substrates.
- Select from four Stand-offs - 20 mm, 50 mm, 50x50 mm Tile and 50 mm C1583
- Environmentally sealed enclosure—weatherproof, dustproof and shockproof—meets or exceeds IP65
- Inexpensive, single-use dollies eliminate cleaning for re-use and can be kept as a permanent record
- Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
- 10, 14, 20 or 50 mm dollies maximize capability and measurement resolution across a wide range of bond strengths
- Calibrated and certified to ± 1% accuracy using a NIST traceable load cell
- Certificate of Calibration showing traceability to NIST included (Long Form)
EN 1542/12004-2, AS/NZS 1580.408.5 and others
Features
Simple
- Easily select dolly sizes, change measurement units, or store readings with the touch of a button
- Inexpensive, single-use dollies and plates eliminate cleaning for re-use and can be kept as a permanent record
- Each kit comes with everything needed for testing
Durable
- Environmentally sealed enclosure—weatherproof, dustproof and shockproof - meets or exceeds IP65
- Hard-shell carrying case included, with optional upgrade to a heavy-duty Pelican case (Automatic models only)
- Two year warranty
BR 27822 
VN 14001 
US 6649 
AR 5029 
MX 3588 
CN 3389 
IQ 2057 
CO 1873 
