METHOD OF EVALUATING ADHESION STRENGTH OF A MULTILAYER COATING Russian patent published in 2020 - IPC G01N19/04 

FIELD: measurement technology.

SUBSTANCE: invention relates to investigation of mechanical properties of coatings, namely, to methods of evaluation of adhesion strength of coating with base. Method involves application of layers of the tested coating on a sample in the form of a metal plate, a plate with a tested coating is applied in a coating of a transverse notch to a substrate and a bend at location of an incision in a stretching area at bending of a plate and evaluation of adhesion strength by results of destruction of a coating. Note here that additional notch is made, wherein notches are arranged symmetrically relative to sample bending symmetry axis, there is prepared a section in plane perpendicular to notch line, and on section it is determined: point O – point of intersection of bisector of sample bending angle αpassing through bend center of sample O', with line perpendicular to surface of coating at point A₁ and passing through point A₁, is carried out from point O through line A₂ of end of section of coating detachment from base and determining angle γ₁ of coating separation from base, then a line is passed from point O through point A₃ of the end of the section of the maximum delamination of the coating layer from the underlying coating layer and an angle of γ_max is determined the angle of maximum delamination of the coating layers, then the line is passed from point O through point A₄ of the end of minimum value of the section of coating layer separation from the underlying coating layer and the angle γ_min – angle of minimum delamination of the coating layers is determined.

EFFECT: providing quantitative and qualitative assessment of adhesion strength between coating and substrate and between layers of multilayer coating.

4 cl, 2 dwg, 1 tbl