Anticrack

Anticrack is a term used in materials science and engineering to describe features or strategies that reduce crack initiation and slow crack growth in a material or structure under mechanical stress. Anticrack properties can be intrinsic to the material’s microstructure or engineered through processing and design. The concept is relevant across metals, ceramics, polymers, composites, and coatings.

Common mechanisms underlying anticrack behavior include crack deflection and bifurcation at interfaces or second-phase particles, which increases the path length and energy required for a crack; crack bridging where intact fibers or particles carry load after matrix cracking; residual compressive surface stresses from processing like tempering or coating deposition, which hinder crack initiation; microcrack toughening where interacting small cracks dissipate energy; and, in some alloys, phase transformation toughening that absorbs fracture energy.

Engineering approaches to promote anticrack behavior encompass creating toughened ceramics with whiskers or particles, fiber-reinforced composites, and coatings that develop or retain compressive surface stress; lattice metamaterials and other architectural designs that steer cracks along non-propagating routes. These strategies aim to increase the energy required for crack growth and improve durability under mechanical or thermal loading.

Applications of anticrack concepts include structural components in aerospace and automotive industries, protective coatings for glass and metals, and electronic packaging where resistance to cracking is important. The field emphasizes improving damage tolerance while managing potential trade-offs in weight, stiffness, cost, or processing complexity.

Limitations and considerations include manufacturing cost and complexity, environmental sensitivity, and the dependence of performance on crack orientation, loading mode, and long-term environmental exposure.