Динамическое индентирование керамики из оксида алюминия

The paper is devoted to investigation of oxide ceramic mechanical behavior during penetration of diamond conical indenter at different time duration of the process: from ~80 microsecond to ~ 100 second in order to determine material sensitivity to the loading rate. Static indentation was produced with Testometric loading machine. Dynamic indentation was produced with the original experimental setup where the sample glued at the end surface of the loading aluminum rod was pushed into non-movable indenter. Loading rod end surface displacement was realized by the propagation of elastic wave initiated by the striker accelerated by pneumatic gun. Tensometry was used to determine the loading rod displacement which is equivalent to the indenter penetration distance in the material. The loading force acting on the sample from the indenter was registered by piezoelectric force sensor. Optical microscopy of the indents allowed us to obtain the relationship between the indentation depth and maximum loading force. Comparison of experimental results obtained on static and dynamic indentation had revealed that at the beginning of the process the mechanical response of material is the same at different loading velocities; at the following stages of loading there is significant deviation of mechanical response of material subjected to dynamic indentation.