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The Hamaker constants of eight different ceramic materials, 6H‐SiC, tetragonal, partially stabilized ZrO2 (3% Y2O3), β‐Si3N4, α‐Al2O3, Y2O3, sapphire (single‐crystal α‐Al2O3), MgO, MgAl2O4, and fused silica, across air, water, and n‐dodecane at room temperature and across silica at 2000 K have been calculated from optical data using the Lifshitz theory. Spectroscopic ellipsometry was used to measure the photon energy dependence of the refractive index, n, and the extinction coefficient, k, in the visible and near‐UV range on several important ceramic materials. This relatively simple, nondestructive technique has proved to yield reliable optical data on sintered, polycrystalline materials such as Si3N4, SiC, ZrO2, Al2O3, and ZnO. For the other materials, Y2O3, sapphire, MgO, MgAl2O4, and fused silica, optical data from the literature were used to calculate the Hamaker constants. The calculated Hamaker constants were estimated to be accurate within ±10%.

The lowered threshold load for cracking with the cube-corner indenter has been used in developing a method that can be used to measure residual stresses in small volume brittle materials. By studying a series of orthogonal cracks generated at loads not exceeding 10 mN with the cube-corner indenter, a variation of crack length with position around a large Vickers impression in soda-lime glass was observed. Using an indentation fracture mechanics approach residual stresses were evaluated at the positions where the cube-corner indents had been made. The stress values thus evaluated were generally higher than those reported in the literature where micro-Vickers indents had been used to measure the stresses. Possible reasons for the disparity are discussed.