The mechanical properties of brick-and-mortar composites depend on their interface fracture properties, which have not been evaluated to date, preventing a rational optimization of the microstructure and of the resulting mechanical properties. Micro-(cantilever) and macro-scale (Single Edge Notched Bending) tests on nacre-like alumina both result in crack initiation at the interface between the platelets. We assess crack initiation and predict the failure force by means of 2D and 3D finite element simulations employing the same fracture modeling approach at both scales, namely the coupled criterion. The interface fracture properties are determined by means of inverse identification based on both micro- and macro-scale experiments. The interface exhibits typical values of 438 MPa tensile strength and 1.96 J/m² fracture toughness. The forces at crack initiation predicted employing these parameters are in good agreement with the forces measured experimentally for both micro- and macro-scale tests. The quantitative determination of the interface fracture properties should help the design and optimization of this class of brick-and-mortar materials.

砖瓦复合材料的机械性能取决于其界面断裂性能，迄今为止尚未进行评估，这妨碍了微观结构和所得机械性能的合理优化。在珍珠质状氧化铝上进行的微观（悬臂式）和宏观（单边缺口弯曲）测试均会导致血小板之间界面处的裂纹萌生。我们通过在两个尺度上使用相同的裂缝建模方法（即耦合准则）的2D和3D有限元模拟来评估裂纹萌生并预测破坏力。界面断裂特性是通过基于微观和宏观实验的逆识别来确定的。该界面的典型值为438 MPa抗拉强度和1.96 J / m ²断裂韧性。使用这些参数预测的裂纹萌生力与微观和宏观测试的实验测得的力非常吻合。界面断裂特性的定量测定应有助于这类实体材料的设计和优化。