Microstructural changes in 3Y-TZP induced by scratching and indentation

Microstructural changes produced in 3Y-TZP by contact with a Vickers indenter during indentation and scratch tests have been studied by μ-Raman spectroscopy and transmission electron microscopy. In the scratch test, the monoclinic phase distribution under the scratch track is maximal at the surface, close to the edges of the groove, where the pile-up is formed by the flow of deformed material. This distribution coincides with the plastic deformed zone observed by electron microscopy. For indentation, the highest concentration of monoclinic phase is found below the imprint at a depth approximately equal to its semi-diagonal, while plastic deformation is concentrated in a narrow region of less than 1 μm just below the indenter tip. The present results show that the microstructural changes induced by the scratch test are similar to those induced during grinding.