Compression test system for a single submicrometer particle

A compression test system was developed for measuring the strength of a single particle with a cross-sectional dimension of less than 1μm. The test system used a small diamond plate that has a flat platen to compress the particle on a diamond substrate. To avoid compressing multiple particles and to avoid direct contact between the platen and the substrate, the flat area was comparable in size to the tested particle. Mechanical processes such as polishing, however, have difficulty in fabricating such a small area. Here, fabrication of a micrometer-sized flat area was achieved by using focused ion beam technology. The resulting compression test system successfully measured the strength of a single submicrometer particle. Results showed that the mean strength of alumina particle with nominal mean diameter of 0.7μm was 2.9GPa.