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1.
Materials (Basel) ; 17(13)2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38998139

ABSTRACT

In this paper, glow nitriding processes at cathode potential are used at various temperatures to investigate how they affect the corrosion resistance of 316L steel in ethanol at temperatures of 22 °C and -30 °C. Lowering the test temperature reduces the corrosion rate of the nitrided layers. Conversely, glow nitriding at 450 °C improves the corrosion resistance of the tested steel. Increasing the nitriding temperature to 520 °C increases the corrosion rate. It should be noted that the ethyl alcohol solution, due to the lack of aggressive ions, does not cause significant changes in the corrosion rate of the steel. The value of the corrosion current varies in the range of 10-2-10-3 µA/cm2. Nitrided layers increase the contact angle measured for water and are entirely wettable for ethanol. The objective of this study is to evaluate the effect of the nitriding temperature of AISI 316L steel on its corrosion resistance in an ethanol solution at room temperature and at -30 °C.

2.
Materials (Basel) ; 16(18)2023 Sep 06.
Article in English | MEDLINE | ID: mdl-37763363

ABSTRACT

The present study elucidates the impact of glow discharge oxidation within a low-temperature plasma environment on the bioactivity characteristics of an NiTi shape memory alloy. The properties of the produced surface layers, such as structure (TEM observations), surface morphology (SEM observations), chemical and phase composition (EDS and XRD measurements), wettability (optical gonimeter), and the biological response of osteoblasts and platelets to the oxidized surface compared with the NiTi alloy without a surface layer are presented. The presented surface modification of the NiTi shape memory alloy, achieved through oxidizing in a low-temperature plasma environment, led to the creation of a continuous surface layer composed of nanocrystalline titanium oxide TiO2 (rutile). The findings obtained from this study provide evidence that the oxidized layer augments the bioactivity of the shape memory alloy. This augmentation was substantiated through the spontaneous biomimetic deposition of apatite from a simulated body fluid (SBF) solution. Furthermore, the modified surface exhibited improved osteoblast proliferation, and enhanced platelet adhesion and activation. This proposed surface modification strategy holds promise as a prospective solution to enhance the biocompatibility and bioactivity of NiTi shape memory alloy intended for prolonged use in bone implant applications.

3.
Materials (Basel) ; 15(20)2022 Oct 14.
Article in English | MEDLINE | ID: mdl-36295226

ABSTRACT

In this paper, we analyze the possibilities of the protection of tools for wood machining with PVD (Physical Vapor Deposition) hard coatings. The nanolayered TiN/AlTiN coating, nanocomposite TiAlSiN coatings, and single layer TiN coating were analyzed in order to use them for protection of tools for wood machining. Both nanostructured coatings were deposited in an industrial magnetron sputtering system on the cutting blades made of sintered carbide WC-Co, while TiN single layer coating was deposited by evaporation using thermionic arc. In the case of TiN/AlTiN nanolayer coatings the thickness of the individual TiN and AlTiN layer was in the 5-10 nm range, depending on the substrate vertical position. The microstructure and chemical composition of coatings were studied by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) method. Additionally, in the case of the TiN/AlTiN coating, which was characterized by the best durability characteristics, the transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) methods were applied. The coatings adhesion to the substrate was analyzed by scratch test method combined with optical microscopy. Nano-hardness and durability tests were performed with uncoated and coated blades using chipboard. The best results durability characteristics were observed for TiN/AlTiN nanolayered coating. Performance tests of knives protected with TiN and TiAlSiN hard coatings did not show significantly better results compared to uncoated ones.

4.
Materials (Basel) ; 14(11)2021 May 22.
Article in English | MEDLINE | ID: mdl-34067369

ABSTRACT

The influence of different types of cemented carbide blades and thickness of TiAlN/a-C:N and TiN/AlTiN protective coatings used in the wood industry on cutting performance has been studied. Three types of WC-Co cemented carbide blades with different cobalt content were used in the study. The thicknesses of both types of coatings were ~2 and ~5 µm. The structure, chemical and phase composition were studied using transmission and scanning electron microscopy (TEM, SEM), X-ray dispersion spectroscopy (EDX) and X-ray diffraction (XRD), respectively. The adhesion was evaluated by scratch test. Nanohardness and durability tests of uncoated and coated blades were performed. We found that the blades covered with 5 µm TiN/AlTiN coatings exhibited the best durability characteristic. The cutting distances were within the range ~6700-~7080 depending on the substrates in comparison with pure substrates (~4300-~4900) and 2 µm TiN/AlTiN coatings (~5400-~6600). The presence of a thin and soft outer a-C:N layer aggravates the nanohardness and durability of the coated blades.

5.
Adv Clin Exp Med ; 27(4): 493-499, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29558044

ABSTRACT

BACKGROUND: The GO-MORE study was an open-label, multinational, prospective study that investigated the efficacy and safety of adding golimumab to synthetic disease-modifying antirheumatic drugs (sDMARDs) in patients with active rheumatoid arthritis (RA). OBJECTIVES: The aim of this study was to assess the efficacy and safety of golimumab add-on therapy in the Polish subpopulation of the GO-MORE study. MATERIAL AND METHODS: Patients were administered 50 mg subcutaneous doses of golimumab once a month for 6 months, while continuing therapy with sDMARDs and/or glucocorticoids (GCS). The primary clinical endpoint was the proportion of patients with moderate or good European League Against Rheumatism (EULAR) response based on the 28-joint disease activity score (DAS28) erythrocyte sedimentation rate (ESR) after 6 months. RESULTS: The Polish subpopulation (129 patients) was similar to the overall study population (3,280 patients) with regard to age, sex, mean baseline DAS28, inflammatory markers, average methotrexate dose, and GCS use; however, they had a longer disease duration (median: 6.04 vs 4.9 years) and more Polish patients (85.9% vs 78.7%) had high disease activity (DAS28-ESR ≥3.2). At 6 months, 84.5% of Polish patients showed good or moderate EULAR response, 26.4% had low disease activity and 17.1% were in clinical remission, compared with 82.9%, 37.4% and 23.9%, respectively, in the overall study population. Golimumab safety profile was consistent with previous studies and comparable to the overall study population. CONCLUSIONS: The addition of golimumab to sDMARD therapy in Polish RA patients showed good or moderate EULAR DAS28-ESR response in 84.5% of patients, mirroring the overall study population.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Methotrexate/therapeutic use , Antirheumatic Agents/administration & dosage , Drug Therapy, Combination , Humans , Methotrexate/administration & dosage , Poland , Prospective Studies , Treatment Outcome
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