In the present study, enamel wear against indirect composite resins was evaluated using two newly designed wear test methods: a rotating sliding wear test and a buff wear test. For the composite resins investigated in this study, their surface morphologies were examined using a scanning probe microscope after buff-polishing. After the wear tests, enamel was worn down by hard fillers that protru...

The Brinell, Vickers, Meyer, Rockwell, Shore, IHRD, Knoop, Buchholz, and nanoindentation methods used to measure the indentation hardness of materials at different scales are compared, and main issues and misconceptions in the understanding of these methods are comprehensively reviewed and discussed. Basic equations and parameters employed to calculate hardness are clearly explained, and the di...

Whereas common Vickers indentation segmentation algorithms are precise with high quality images, low quality images often cannot be segmented appropriately. We investigate an approach, where unfocused images are segmented. On the one hand, the segmentation accuracy of low quality images can be improved. On the other hand we aim in reducing the overall runtime of the hardness testing method. We ...

In the present work, the processing and characterization of electroconductive Alumina-TiC-Ni nanocomposites obtained by Spark Plasma Sintering (SPS) are described. These nanocomposites are singular due to the excellent mechanical properties they present (particular regarding Vickers hardness, 25.6 ± 0.7 GPa), as well as their extremely good wear behaviour, studied under “ball-on-disk” dry slidi...

The mechanical properties of the high-strength low-alloy pipeline steels were mainly controlled by the subsequent phase transformations after rolling. The influence of hot uniaxial compression on the phase transformation of acicular ferrite was explored by viewing of the deformation degree, the deformation temperature, and the strain rate. The results show that the increase of deformation amoun...

The Vickers hardness of the cross-sectioned area of titanium castings made from an experimental resin-bonded calcia investment and three commercial investments was evaluated. The microstructure and element distribution of the surface zone were analyzed using an EPMA. The results showed that the high hardness of the casting surface could be decreased using the experimental investment. The hardne...

Influence of the shaping effect on hardness homogeneity by Vickers indentation analysis B. Guillaume a,∗, F. Boschini a, A. Rulmont a, M. Ausloos b, R. Cloots a a Laboratoire de Chimie Inorganique Structurale, SUPRATECS, Department of Chemistry, Chemistry Inst. B6, University of Liège, Sart-Tilman, B-4000 Liège, Belgium b Physique Statistique et des Matériaux, SUPRATECS, Department of Physics, ...

Recently, a method for evaluating the fracture toughness of ceramics has been proposed by Fett based on the computed crack-opening displacements of cracks emanating from Vickers hardness indentations. To verify this method, experiments have been conducted to determine the toughness of a commercial silicon carbide ceramic, Hexoloy SA, by measuring the crack-opening profiles of such Vickers inden...