Design of a bio-inspired composite using probabilistic fracture mechanics

Area of Science:

• Materials Science
• Mechanical Engineering
• Biomimetics

Background:

• Bio-inspired composites like nacre and bone exhibit superior strength and toughness due to their staggered hard inclusions and soft interfaces.
• The mechanical properties of these composites are highly dependent on the critical overlap ratio of inclusions, a key design parameter.
• Real-world applications often involve inherent randomness in material and geometrical parameters.

Purpose of the Study:

• To investigate the influence of parameter randomness on the critical overlap ratio in 2D and 3D bio-inspired composites.
• To develop a probabilistic framework for determining the critical overlap ratio under various uncertainties.
• To propose a design factor of safety accounting for parameter variations.

Main Methods:

• Probabilistic methods were employed to analyze the critical overlap ratio for both two-dimensional (2D) and three-dimensional (3D) inclusions.
• For 3D cases lacking analytical solutions, the high-dimensional model representation technique combined with finite element analysis was utilized.
• Monte Carlo Simulation was implemented to assess the probability of failure in both 2D and 3D scenarios.

Main Results:

• The study successfully determined the critical overlap ratio for bio-inspired composites considering parameter randomness.
• Probabilistic analysis revealed the impact of uncertainties on the composite's performance.
• A novel factor of safety for the critical stress intensity factor was proposed.

Conclusions:

• The critical overlap ratio is a crucial parameter influenced by randomness in bio-inspired composites.
• The developed probabilistic approach and simulation techniques provide a robust method for analyzing composite behavior.
• The proposed safety factor aids in designing reliable bio-inspired composite structures by accounting for inherent uncertainties.