Analytical stress analysis of the furan epoxy composite coatings subjected to tensile test.

The presence of reliable techniques for predicting the stress state in composite materials is one of the most important requirements in the design of composite components and structures. An analytical model has been developed to evaluate the shear stresses at the substrate-coating interface in tensile testing of a flat specimen. The developed model has been verified by numerical simulation. The strength and mechanisms of the fracture of furan epoxy composite coatings with polyvinyl chloride and zinc oxide fillers with various concentrations were studied. The adhesion strength of furan epoxy composite coatings with metal substrate was determined by the pull-off test of cylindrical specimens and the tensile test of flat-coated specimens. The correlation between the measured values of fracture stresses for two types of tests of composite coatings was determined. It is concluded that for qualitative comparison of fracture stress in composite coatings it is possible to neglect stress concentration in the specimens. The analyzed methods of stress evaluation have the same trends in the change of the measured values for different composite coatings. However, considering the stress concentration in the specimens provides more accurate results in determining the strength characteristics. [ABSTRACT FROM AUTHOR]