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We report a comparative study of single-layer (TiAlCrSiY)N and multilayer (TiAl-CrSiY)N/(TiAlCr)N PVD coatings on cutting tools during the break-in stage of high-speed dry cutting. Phase and chemical composition of tribooxides forming in the coating wear area were studied by X-ray photoelectron spectroscopy. It is shown that amorphous oxide films with a thickness of several dozen angstroms contain phases with a chemical composition close to mullite, sapphire, rutile, and chromium oxide. As a result of selective wear, the contact surface of the coatings retains the most durable tribooxides carrying out protective functions. Low-cycle fatigue resistance is studied using the cyclic microindentation technique. Fractal analysis of time-resolved indenter penetration depth curves combined with scanning electron microscopy (SEM) demonstrates phenomenological regularities of coatings’ damageability at the early stage of wear. It is shown that, in comparison with single-layer (TiAlCrSiY)N, the nucleation and growth of microcracks in a multilayer (TiAlCrSiY)N/(TiAlCr)N coating is accompanied by acts of microplastic deformation providing a higher fracture toughness of the (TiAlCrSiY)N/(TiAlCr)N multilayer nanocomposite.

Lead sulfide (PbS) crystals with sizes from 20 to 500 nm were deposited in chemical bath from an alkaline solution (CBD method). The morphology of specimens was studied using high resolution scanning electron microscopy (HRSEM). Influence of crystallite sizes on the electronic structure was studied with X-ray photoelectron spectroscopy (XPS) and high resolution electrons energy losses spectroscopy (HREELS). The work function was measured with a Kelvin probe microscopy in air.

New accurate data of the neutron-proton spin-dependent total-cross-section difference ΔσL(np) at the neutron-beam kinetic energies 1.39, 1.69, 1.89, and 1.99 GeV are presented. In general, these data complete the measurements of energy dependence of ΔσL(np) over the Dubna Synchrophasotron energy region. Measurements were carried out at the Synchrophasotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research. The quasi-monochromatic neutron beam was produced by breakup of extracted polarized deuterons. The deuteron (and hence neutron) polarization direction was flipped every accelerator burst. The initial transverse (with respect to beam momentum) neutron polarization was changed to a longitudinal one and longitudinally polarized neutrons were transmitted through the large proton longitudinally polarized target. The target polarization direction was inverted after one to two days of measurements. Four different combinations of the beam and target parallel and antiparallel polarization directions, both oriented along the neutron-beam momentum, were used at each energy. A fast decrease in −ΔσL(np) with increasing energy above 1.1 GeV and a structure in the energy dependence around 1.8 GeV, first observed from our previous data, seem to be well revealed. The new results are also compared with model predictions and with phase-shift analysis fits. The ΔσL quantities for isosinglet state I = 0, deduced from the measured ΔσL(np) values and known ΔσL(pp) data, are also given. The results of the measurements of unpolarized total cross sections σ0tot(np) at 1.3, 1.4, and 1.5 GeV and σ0tot(nC) at 1.4 and 1.5 GeV are presented as well. These data were obtained using the same apparatus and high-intensity unpolarized deuteron beams extracted either from the Synchrophasotron or from the Nuclotron.