Cover Photograph: (Top Left) The polarization optical microscope images show the formation of crystalline microarchitectures in Na₂Mn_0.9Fe_0.1P₂O₇ glass formed by laser irradiation. Formed crystal is one of the promising cathode active materials for sodium‐ion batteries. There are two structural polymorphs (beta‐ and layered‐ ) and can selectively form either of them according to the power of laser irradiation. Honma et al. DOI: 10.1111/ijag.14102. (Bottom Right) The apparent indentation fracture toughness of the silver and enamel layers deposited onto a glass substrate have been evaluated via SEM and high resolution surface topography images of the hardness imprints. The imprints are generated by nano‐indentation technique using a cube‐corner indenter. The determination of the fracture toughness by indentation consists in measuring the lengths of the cracks at the corners of the hardness impression. The absence of radial‐median cracks at the indents performed onto sintered silver provides clear evidence of the higher fracture toughness compared to enamel and glass, but prohibits a quantitative comparison. The soda‐lime silicate glass substrate has a homogeneous microstructure ensuring high repeatability onto the radial‐median cracks lengths resulting from the indentation. The average fracture toughness of the enamel layer is relatively complex to assess due to the multiphase microstructure. Walch and Roos DOI: 10.1111/ijag.13875.

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封面图片，第11卷，第1期

封面照片：（左上）偏振光学显微镜图像显示了在通过激光辐照形成的Na ₂ Mn _0.9 Fe _0.1 P ₂ O ₇玻璃中晶体微结构的形成。形成的晶体是钠离子电池极有希望的正极活性材料之一。有两种结构多晶型物（β-和layered-），可以根据激光辐照的能力有选择地形成它们中的任何一个。Honma等。DOI：10.1111 / ijag.14102。（右下）已经通过SEM和硬度印记的高分辨率表面形貌图像评估了沉积在玻璃基板上的银和搪瓷层的表观压痕断裂韧性。压印是使用立方角压头通过纳米压痕技术生成的。通过压痕确定断裂韧性在于测量硬度压痕拐角处的裂纹的长度。与搪瓷和玻璃相比，在烧结银上压痕处不存在径向中性裂纹，这提供了明显的证据，表明其断裂韧性比搪瓷和玻璃更高，但禁止进行定量比较。钠钙硅酸盐玻璃基板具有均匀的微观结构，可确保在压痕导致的径向中间裂纹长度上具有较高的可重复性。由于多相微观结构，搪瓷层的平均断裂韧性相对较难评估。Walch和Roos DOI：10.1111 / ijag.13875。