Determination of coating adhesion
US5838446A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1997 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | May 16, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/0427
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An infrared laser is used to irradiate a sample, which preferably comprises a substrate, onto which an opaque basecoat is applied, which basecoat in turn is coated with a clearcoat. The laser pulse photoablates the basecoat at an interface between the basecoat and the clearcoat, and a blister forms in the clearcoat due to an increase in pressure from the ablation. The irradiation can be done a number of times on fresh areas of the sample and with increased laser energy. A critical energy value is determined which is the energy where a crack begins to propagate from the blister formed. Another laser is used to measure the amount of light reflected off the top surface of the blister which passes through the middle of an aperture. These values, along with others such as the size of the blister and the modulus of the clearcoat, are used to determine the adhesion strength at the interface of the basecoat and clearcoat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.