The effect of ion-exchange on the fracture behavior and the threshold load is investigated for radial crack initiation resulting from cube-corner indentation. Both tin and air sides of the sodium aluminosilicate float glass are considered. The threshold load and mechanical properties are experimentally measured by nanoindentation. A qualitative explanation of crack initiation is developed by analyzing the stresses at the indentation site. The ion-exchanged glasses show a lower threshold load for radial crack initiation with a cube-corner indenter than the raw glass, and this is due to a higher crack driving stress for ion-exchanged glasses. However, the compressive stress on the surface of the ion-exchanged glasses can inhibit the expanding of the radial cracks. The air side always shows higher values for the threshold load than the tin side before and after ion-exchange, which is in accordance with the calculated crack driving stress results.

中文翻译：

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离子交换钠铝硅酸盐玻璃纳米压痕裂纹萌生的新见解

研究了离子交换对由立方角压痕引起的径向裂纹萌生的断裂行为和阈值载荷的影响。钠铝硅酸盐浮法玻璃的锡面和空气面都被考虑在内。阈值载荷和机械性能通过纳米压痕实验测量。裂纹萌生的定性解释是通过分析压痕部位的应力而得出的。与原始玻璃相比，离子交换玻璃的立方角压头产生径向裂纹的阈值载荷较低，这是由于离子交换玻璃的裂纹驱动应力更高。然而，离子交换玻璃表面的压应力可以抑制径向裂纹的扩展。