Multi-scale mechanical characterization of the lining canvas of The Night Watch by Rembrandt

This contribution presents a multi-scale experimental analysis of the mechanical properties of the lining canvas of The Night Watch (1642), a large-format canvas painting by Rembrandt van Rijn. The original canvas has deteriorated significantly, leaving the lining canvas as the primary load-bearing component. Mechanical properties, including Young's modulus, tensile strength, and strain at fracture, are evaluated at three hierarchical levels (fibre, thread, canvas) using advanced in-situ tensile testing combined with optical profilometry, optical microscopy, and Digital Image Correlation. The study distinguishes between the composite properties of the lining canvas, reflecting the combined behaviour of fibres, wax resin, and voids, and the intrinsic properties, representing the fibre material alone. Scaling laws are established to relate stiffness and tensile strength to the characteristic material length scale, enabling predictions of canvas-scale behaviour from non-invasive fibre-level analyses. These findings may inform future conservation strategies for the canvas of The Night Watch and other paintings.