随机薄片网络的单轴拉伸强度及缺口不敏感性

Plate-like network materials randomly assembled from high-strength sheets have unique properties and numerous applications. However, the network has significant random and discrete characteristics, and the mechanism of the influence of these characteristics on the strength and toughness of the material remains unclear. This study aims to elucidate the damage failure evolution process of random sheet network materials under uniaxial tensile load is systematically studied. The notch insensitivity of the strength of such materials is determined, and its mechanism is revealed. This study shows that the interlayer connections have uneven strength and are randomly distributed because of the random and discrete characteristics of the network material. Therefore, in the uniaxial tensile process, damage starts from the weak connection, distributes discretely at multiple points in space, and eventually converges to the main crack, thus making the network exhibit ductile fracture characteristics. Owing to the multipoint distribution of initial damage and the limited stress concentration at the notch tip, the strength of the random sheet network is insensitive to the notch and independent of the toughness of the sheet and interlayer connection.