The fracture toughness of Al/SiC nanolaminates with different layer thicknesses (in the range 10 to 100 nm) was measured by means of micropillar splitting and bending of a notched beam. The crack plane was perpendicular to the layers in the former while notched beams with the notch parallel and perpendicular to the layers were milled in the latter. It was found that crack propagation parallel to the layers took place along the metal–ceramic interfaces and the toughness increased with the layer thickness due to the contribution of the plastic deformation of the Al layers. Crack propagation perpendicular to the layers showed evidence of crack deflection/arrest at the interface. The toughness in this orientation increased as the layer thickness decreased due to the higher density of interfaces except for the nanolaminates with 10 nm layer thickness. In this latter case, crack propagation took place along the weak columnar grain boundaries, leading to a marked reduction in toughness.

通过微柱分裂和切口梁的弯曲来测量具有不同层厚度（在10至100 nm范围内）的Al / SiC纳米层压板的断裂韧性。裂纹平面垂直于前者中的层，而在切口中平行于且垂直于层的切口梁被铣削。结果发现，平行于各层的裂纹扩展是沿着金属-陶瓷界面发生的，并且由于Al层塑性变形的作用，韧性随层厚度的增加而增加。垂直于各层的裂纹扩展显示出在界面处的裂纹偏转/滞留的迹象。该取向的韧性随着层厚度的减小而增加，这归因于除了具有10 nm层厚度的纳米层合物以外的更高的界面密度。