The scratch test is a very powerful technique for measuring hardness at very shallow penetration depths. In the present work, the scratching protocol and data analysis were extended by combining the initial surface profile, the instrument compliance, thermal drift and indenter displacement during the test, which allows reconstruction of the complete indenter trajectory during the scratch test. The analysis of such a diagram leads to the in situ estimation of pile-up sizes and their influence on the area of contact between the indenter and the material. As a result, criteria for a scratch width estimation algorithm can be formalized as well as scratching contact depth can be derived. Based on the indenter apex shape characterized with scanning probe microscopy, it has been shown that lateral elastic recovery takes place during the scratch test. The proposed analysis was applied to the measurement of scratch hardness for several materials known for different piling and elastic recovery behavior during mechanical testing.

The structure evolution of the Zr 50 Ni 18 Ti 17 Cu 15 massive metal glass upon megaplastic strain (MPS) in the Bridgeman chamber is investigated in a wide interval of strain degrees at room temperature. It is demonstrated that upon MPS with n = 1/2 rotation of the Bridgeman anvil, nanocrystalline phases are precipitated in the alloy. With increasing strain, these phases are dissolved. It is suggested that nucleation centers of nanocrystalline phases (nanoclusters) are formed in the amorphous matrix upon MPS under compression without shear in the Bridgeman chamber. These phases grow in the shear bands transforming into the nanocrystalline phase upon MPS.