PAINT AND COATINGS LABORATORY

Paint and Corrosion Adhesion Testing

Coating Specimen After Impact Testing

Touchstone's Mechanical Testing Laboratory offers a variety of both standard and custom tests which can be used to measure resistance to cracking (flexibility) and adhesion of attached organic coatings on substrates of sheet metal or rubber-type materials. Among them are:

• Direct and Reverse Impact Test (ASTM D2794) [Shown above]
• T-Peel Test
• Direct Tensile Testing (ASTM D5179)
• Mandrel Bend Tests (ASTM D522)
• Olsen Cup Tests
• Bend Test (ASTM D4145)
• Peel Test (ASTM B571)
• Tape Test (ASTM D3359) [Described below]

Measuring Adhesion by Tape Test (ASTM D 3359)

"Standard Test Method for Measuring Adhesion by Tape Test"

ASTM D3359 provides two test methods for assessing the adhesion of coating films to metallic substrates by applying and removing pressure-sensitive tape over cuts made in the film.

In Test Method A, an "X-cut" is made in the film to the substrate, pressure-sensitive tape is applied over the cut and then removed, and adhesion is assessed qualitatively on a 0 to 5 scale.

In Test Method B, a lattice pattern with either six or eleven cuts in each direction is made in the film to the substrate, pressure-sensitive tape is applied over the lattice and then removed, and adhesion is evaluated by comparison with descriptions and illustrations.

Method A is primarily intended for use at job sites, while Method B is more suitable for use in the laboratory. The cross-hatch test, Method B, is not considered suitable for films thicker than 5 mils (125 micometers).

Index of Paint and Coatings Laboratory