Mechanical indentation tester designed to control and measure in real time the microhardness process

A microhardness testing instrument that permits the analysis control of the indentation process in real time is described. To illustrate the technique, a time-dependent microhardness experiment on linear low density polyethylene and poly(methyl methacrylate) was studied. Experimental values of the depth of indentation were obtained for the load-on and load-off processes The analysis of the experimental measurements of depth recovery shows a very quick quasi-elastic recovery followed by a delayed recovery which are controlled by two different processes.