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Monitorowanie początkowego zużycia frezów węglikowych o ostrych krawędziach skrawających

Wolszczak P., Płaska S., Korbiel T., Stachowicz D.

Mechanik

2012

R. 85, nr 1CD

W artykule przedstawiono wyniki monitorowania zużycia nowych narzędzi, którymi były frezy z węglików spiekanych. Testowano przydatność par materiałów pochodzących od różnych producentów o zawartości kobaltu 10 % i 12 %. Obserwację prowadzono z użyciem czujników drgań umieszczonych na głowicy frezarki sterowanej numerycznie. Zaobserwowano przyspieszone zużycie narzędzi na początku ich pracy

The article presents the monitoring results of the wear of new tools, which were ce-mented carbide cutters. There are tested suitability of pairs of materials derived from different manufacturers with a cobalt content of 10 % and 12 %. Observation was carried out using vibration sensors placed on the head of numerically controlled milling machine. Tool wearing was observed at the beginning of their work.

The principle of multilayer plane-parallel structure antireflection

Kosoboutskyy P., Karkulovska M., Morgulis A.

Optica Applicata

2010

Vol. 40, nr 4

759--765

The principle of two- and three-layer transparent system antireflection is based on the method of Fabry–Perot multiple-beam interference spectrum envelopes and it is shown that the presence of half-wave and quarter-wave layer thicknesses or their combination is sufficient but not necessary for its achievement. The necessary condition is the condition of overlapping of interference layer envelopes, therefore the antireflection effect can be observed at arbitrary ratios of optical layer thicknesses, angles of incidence and optical refraction index of media when the condition is satisfied for the minimum of interference contour in the required spectral region.

Interfaces as design tools for short-period InAs/GaSb type-II superlattices for mid-infrared detectors

Szmulowicz F., Haugan H. J., Brown G. J., Mahalingam K., Ullrich B., Munshi S. R., Grazulis L.

Opto-Electronics Review

2006

Vol. 14, No. 1

71-77

The effect of interface anisotropy on the electronic structure of InAs/GaSb type-II superlattices is exploited in the design of thin-layer superlattices for mid-IR detection threshold. The design is based on a theoretical envelope function model that incorporates the change of anion and cation species across InAs/GaSb interfaces, in particular, across the preferred InSb interface. The model predicts that a given threshold can be reached for a range of superlattice periods with InAs and GaSb layers as thin as a few monolayers. Although the oscillator strengths are predicted to be larger for thinner period superlattices, the absorption coefficients are comparable because of the compensating effect of larger band widths. However, larger intervalence band separations for thinner-period samples should lead to longer minority electron Auger lifetimes and higher operating temperatures in p-type SLs. In addition, the hole masses for thinner-period samples are on the order the free-electron mass rather than being effectively infinite for the wider period samples. Therefore, holes should also contribute to photoresponse. A number of superlattices with periods ranging from 50.6 to 21.2 Å for the 4 µm detection threshold were grown by molecular beam epitaxy based on the model design. Low temperature photoluminescence and photoresponse spectra confirmed that the superlattice band gaps remained constant at 330 meV although the period changed by the factor of 2.5. Overall, the present study points to the importance of interfaces as a tool in the design and growth of thin superlattices for mid-IR detectors for room temperature operation.