The microscale growth layers between nacre possess distinctive aragonite structures, including columns, spherulites and organic matrices. High temporal resolution experiments were performed to elucidate the tensile and shear behavior of growth layers under dry and hydrated conditions. For a comparison, pure nacre was tested in corresponding conditions. For both nacre and growth layers, the presence of water enabled larger deformation of hydrated specimens than those of dry specimens. Hydrated growth layers exhibited lower strengths and larger failure strains than hydrated nacre under both shear and tensile loadings. Hydrated growth layers exhibited lower work-to-failure than hydrated nacre under shear, whereas they exhibited higher work-to-failure than hydrated nacre under tension. This work could further our understandings on the interfacial behavior of laminated natural materials, and may help the creation of high performance hierarchical composites.

珍珠层之间的微尺度生长层具有独特的文石结构，包括柱状，球晶状和有机基质。进行了高时间分辨率的实验，以阐明在干燥和水合条件下生长层的拉伸和剪切行为。为了进行比较，在相应条件下测试了纯珍珠母。对于珍珠层和生长层，水的存在都使得水合标本比干燥标本具有更大的变形。在剪切和拉伸载荷下，水合生长层均比水合珍珠质具有更低的强度和更大的破坏应变。水合生长层在剪切作用下比水合珍珠质的失效失败率低，而水合生长层在张力作用下比水合珍珠层的失效失败率更高。