PCS Coating Failure Analysis and Remediation

Question 1

What is the most common root cause of coating delamination from a steel substrate?

Accepted Answer

Inadequate surface preparation

Answer

Excessive dry film thickness

Answer

High ambient humidity during application

Answer

Insufficient mixing of coating components

Question 2

Which type of coating failure is characterized by dome-shaped hollow projections rising from the coating surface?

Accepted Answer

Blistering

Answer

Chalking

Answer

Cratering

Answer

Alligatoring

Question 3

Which coating defect results from UV degradation of the organic binder, leaving loose pigment particles on the surface?

Accepted Answer

Chalking

Answer

Checking

Answer

Sagging

Answer

Pinholing

Question 4

Which condition most commonly causes pinholes (holidays) to form in an applied coating?

Accepted Answer

Solvent entrapment during curing

Answer

Over-application of coating

Answer

Low substrate temperature

Answer

Excessive dry film thickness

Question 5

What is the term for a coating failure in which paint separates from the substrate or underlying coat in large continuous sheets?

Accepted Answer

Delamination

Answer

Flaking

Answer

Erosion

Answer

Spalling

Question 6

Which standardized test method is used to evaluate coating adhesion by making a crosshatch cut and applying tape per ASTM D3359?

Accepted Answer

Cross-cut adhesion test

Answer

Dry film thickness measurement

Answer

Holiday detection test

Answer

Pull-off adhesion test

Question 7

Alligatoring (crocodile cracking) of a coating surface is typically caused by which condition?

Accepted Answer

Application of a hard topcoat over a soft, incompletely cured primer

Answer

Excessive surface profile roughness

Answer

Application in cold weather below 50°F

Answer

Insufficient pigment-to-binder ratio