An analysis of size effects and doping on the strength of ultrananocrystalline diamond (UNCD) thin films is presented. The doping was achieved by the addition of nitrogen gas to the Ar/CH4 microwave plasma. The strength data, obtained by means of the membrane deflection experiment (MDE) were interpreted using Weibull statistics. The validity and predictive capability of the theory were examined...

Three-dimensional (3D) printed polypropylene (PP) structures mechanically reinforced with antimony doped tin oxide (ATO) nanoparticles (NPs) at various concentrations were developed and fully characterized. Nanocomposite filaments produced by an optimized melt mixing extrusion process, utilized as feedstock for the Fused Filament Fabrication (FFF) of specimens. Samples 3D assessed via mechanica...

This article presents an experimental study on the fatigue behaviour of cracks emanating from cold-expanded holes utilizing thermoelastic stress analysis (TSA) and synchrotron X-ray diffraction (SXRD) techniques with the aim of resolving the long-standing ambiguity in the literature regarding potential relaxation, or modification, of beneficial compressive residual stresses as a result of fatig...

The use of reciprocating movement (RM) was claimed to increase the resistance of nickel-titanium (NiTi) file to fatigue in comparison to continuous rotation (CR). Recently two new brands of NiTi file have been marketed for use in a RM mode. The purpose of this study was to compare the cyclic fatigue resistance and torsional resistance of these two files; Reciproc and WaveOne. Cyclic fatigue tes...

Toughness is a complex material characteristic that is viewed from multiple aspects and is influenced by numerous factors. It is very important to have ability to assess toughness, i.e. to determine ductile or brittle material behaviour at any specific time. Beside total impact energy obtained at Charpy instrumented pendulum, the use of additional parameters such as lateral extension measuremen...

A dual phase Ti-6A1-4V alloy was tested in uniaxial tension over a large quasi-static loading range (10−5–10−1 s−1) in ambient environment. As strain rate increases, strength of the alloy was found to increase at the expense of ductility. In the low strain-rate region, strain rate sensitivity of the material experienced a gradual decrease during plastic deformation. In the high strain-rate regi...

Fatigue crack growth damage mechanisms for nickel-based superalloys at high, negative stress ratios challenge classical tip shielding and closure concepts. rate single-edge notch Ni-based superalloy 718 specimens 100 °C were evaluated several (0.5, 0.1, ?1, ?2). Multiple methods used to calculate the effective driving force rates in region II (i.e., Paris or power law regime). The relationships...