Prediction of delamination in multilayer artist paints under low amplitude fatigue loading

• Calibration of constitutive equations of alkyd paint and acrylic ground.
• T-peel testing and analysis for alkyd/acrylic cohesive zone model calibration.
• Mixed mode irreversible cohesive zone modelling for cyclic loading scenarios.
• Time (years) to initiate/propagate interface cracks under moisture/mechanical loads.

The objective of this study is to model the effect of low amplitude cyclic stresses on multilayer paint systems found in works of art. Acrylic gesso grounds with superimposed alkyd paint layers on canvas were investigated. Data from uniaxial testing of free-standing paint films was used to determine the constitutive properties of the paint. Peel tests were performed to determine the cohesive zone properties of the paint interface. A finite element model of a coating on a primed canvas substrate was subjected to combined cyclic and static mechanical loadings typically experienced by fine art paintings. Interface separation was controlled by an irreversible cohesive zone model that includes damage accumulation due to cyclic loading. Fatigue crack initiation times in years were predicted for various conditions including ordinary and extreme histories that paintings may experience in museum and conservation settings.