Microhardness tester

The Vickers hardness test was performed according to the C1327 standard using a Mitutoyo microhardness tester (Mitutoyo, Takatsu-ku, Japan) under a force of 1 kg for composite resins and 2 kg for glass ceramics for a constant indenter dwell time of 15 s. We selected two random points on each sample for hardness measurements (five samples per group). All indentation tests were performed under ambient laboratory conditions. After indentation, the hardness value of each material was obtained by calculating the diagonal length of each square indentation. Subsequently, we used an image analyzer (Leica DM 2500M, Leica Microsystems, Wetzlar, Germany) to observe the indentations.

German made; Mitutoyo microhardness tester was used under low-force hardness scale (HV 0.2) with a test force-load of 1.96 N for a dwell time of 10 s. The microhardness was figured thrice at distinct points, and an average value was noted for the calculation. The EDMed sample with superior output responses and correlated to tribological performance was cut cross-sectionally for measuring the recast layer thickness. The diamond paste was utilized for the mirror-polished of the substrate. The surface morphological investigation of a cross-section of the EDMed substrate depicted the recast layer thickness that was measured at five different positions at the transverse section and its average value was recorded.