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Abstract: Oxidation protective SiC nanowires‐reinforced SiC (SiCNWs‐SiC) coating was prepared on pack cementation (PC) SiC‐coated carbon/carbon (C/C) composites by a simple chemical vapor deposition (CVD) process. This double‐layer SiCNWs‐SiC/PC SiC‐coating system on C/C composites not only has the advantages of SiC buffer layer but also has the toughening effects of SiCNWs. The microstructure and phase composition of the nanowires and the coatings were examined by SEM, TEM, and XRD. The single‐crystalline β‐SiC nanowires with twins and stacking faults were deposited uniformly and oriented randomly with diameter of 50‐200 nm and length ranging from several to tens micrometers. The dense SiCNWs‐SiC coating with some closed pores was obtained by SiC nanocrystals stacked tightly with each other on the surface of SiCNWs. After introducing SiCNWs in the coating system, the oxidation resistance is effectively improved. The oxidation test results showed that the weight loss of the SiCNWs‐SiC/PC SiC‐coated samples was 4.91% and 1.61% after oxidation at 1073 K for 8 hours and at 1473 K for 276 hours, respectively. No matter oxidation at which temperature, the SiCNWs‐SiC/PC SiC‐coating system has better anti‐oxidation property than the single‐layer PC SiC coating or the double‐layer CVD SiC/PC SiC coating without SiCNWs. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis (TGA) and mass spectrometry (MS) of initial steam oxidation at 650 °C in Ar + 40% H2O for 150 h of the P92 steel with and without aluminum‐silicon‐CVD coating were investigated. We deposited Al‐Si coating on ferritic/martensitic (F/M) P92 steel using the chemical vapor deposition in a fluidized bed reactor (CVD‐FBR) at 580 °C for 2 h and subsequently heat‐treated in Ar at 700 °C for 2 h. The thermodynamic software Thermo‐Calc was used for theoretical simulations in equilibrium under similar experimental oxidation conditions from 500 to 900 °C. TGA verified that the P92 steel coated with Al‐Si had not gained weight compared to the uncoated oxidized P92 steel that gained 5.25 mg/cm2. The coated sample, with protective oxide layers, i.e., silica (SiO2) and alumina (Al2O3) on the diffusion zone, was better protected during steam oxidation. Al‐Si‐CVD‐FBR coating helped to delay catastrophic oxidation and avoid loss of chromium from steel through volatilization. SEM: EBSD/EDAX and XRD were used to study morphology/composition and structure of the samples. [ABSTRACT FROM AUTHOR]

This report is the first describing experimental evaluation of Fano factor for diamond detectors. High-quality self-standing chemical vapor deposited diamond samples were produced using lift-off method. Alpha-particle induced charge measurements were taken for three samples. A 13.1 ±0.07 eV of the average electron-hole pair creation energy and excellent energy resolution of approximately 0.3% were found for 5.486 MeV alpha particles from an 241Am radioactive source. The best Fano factor for 5.486 MeV alpha particles, calculated from experimentally obtained epsilon values and the detector intrinsic energy resolution, was 0.382 ± 0.007. [ABSTRACT FROM AUTHOR]

A modified fluidized bed reactor is developed to homogenously coat micrometer-sized particles with reactive polymer films using CVD. This technique is found to be rapid (~30min per batch) and scalable (up to 1g particles), and can create homogenous coatings on microparticles down to 10 mm in diameter. By tuning critical variables, such as working pressure and the carrier gas flow rate, full coverage of a reactive polymer film can be realized. Janus particles are synthesized and can be visualized via fluorescence microscopy. [ABSTRACT FROM AUTHOR]

This paper reports the atmospheric pressure chemical vapor deposition of vanadium oxide coatings using vanadyl (IV) acetylacetonate at 500 oC. The as-grown samples for 0.8 L min-1 O2 flow rate showed an (022)-oriented single vanadium dioxide monoclinic phase of low crystallinity. The narrowest hysteresis width is observed for the particular flow rate indicating a dependency on the shape of the grown crystallites. Regarding the difference in transmittance is determined by the enhanced presence of short- and long-range bond ordering of the samples. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Research on high-performance CVD coatings follows the target to increased hardness and oxidation resistance. Such coatings and coating systems are required for machining tools to optimize the manufacturing parameters for new materials and new processes. The use of chromium-containing coatings is requested because of its feature to increase the corrosion resistance. The production of various chromium-containing coatings is already shown by PVD, but for industrial scale CVD processes there are problems with the chromium precursors. Especially the chromium chlorides have a low vapour pressure and therefore high temperatures are needed for evaporation. To overcome the disadvantages of CrCl3 the relatively good evaporation of halide complexes was reported, showing potential for new CVD processes. Numerous metal compounds form gaseous complexes with Aluminium chloride but also Cr. Based on this characteristic the transport reaction of CrCl2/Al2Cl6 as chromium tetrachloraluminate is investigated. The focus of this work lies in the preparation of the chromium precursors as well as in the optimization of the transport reaction which required various changes in the conventional experimental CVD-setup. To measure the amount of transported chromium the gas phase was condensed and their Cr-content was analyzed. For the CVD deposition of Cr containing coatings, this precursor gas flow can be used directly. Further the interaction between aluminum chloride and the chromium precursor, different process parameters, as well as existing difficulties regarding the transport reaction are discussed. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Nanographite films produced by direct current plasma enhanced chemical vapour deposition technique were covered by metal oxides TiO2 and Al2O3 using atomic layer deposition. Nanographite films are composed of few-layer graphene nanowalls and nanoscrolls, which are mostly oriented perpendicular to the silicon substrate surface. The nanographite and nanographite-metal oxide composite film materials, with oxide layer thickness between 50 nm and 250 nm, were characterized by scanning electron microscopy, energy dispersive X-ray analysis, thermal gravimetric analysis, and Raman spectroscopy. We demonstrate that the metal oxide deposit homogenously covers graphene nanowalls and forms individual spherical particles on the surface of needle-like nanoscrolls. Field emission properties of the samples were measured in a flat vacuum diode configuration. It was found that the metal oxide layers thinner than 200 nm do not significantly affect the field emission characteristics of the nanographite. At the same time, metal oxides form a passivation shell which may improve the nanographite film performance as cold cathode in vacuum electronic devices. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

In this paper, flame-pyrolytic treatment methods of metal surfaces are compared to vacuum-based CVD processes. There is a practical consideration of the aforementioned methods. The layers formed were analyzed by scanning electron microscopy, changes in properties such as surface energy and adhesion of subsequent layers of paint were detected by measurement. [ABSTRACT FROM AUTHOR]

Chemical vapour deposition (CVD) of diamond surface layers is an effective way of improving the properties of cemented carbide cutting tools. Inadequate coating adhesion is one of the main issues and it may be affected by the residual stresses of the CVD diamond films. The most common methods for nondestructive residual stress analysis are based on X-ray diffraction. The present paper deals with the particular case of determining the residual stress state of thin CVD diamond layers deposited on cobalt cemented tungsten carbide (WC-Co) substrates. It will be shown that the application of the conventional sin2ψ method might lead to erroneous results, as a result of superimposing diffraction lines originating from cobalt and the diamond coating. An approach to separating information on the substrate and film, based on grazing conditions in the symmetrical Ψ mode of diffraction, is presented. The results, revealing large compressive stresses within the coating, are compared with those obtained by supplementary micro-Raman spectroscopy investigations. [ABSTRACT FROM AUTHOR]

Dear participants of EuroCVD20, with pleasure we address you some words about the present conference proceedings of EuroCVD20. We faced a big challenge organizing a conference to which the full paper peer reviewed contributions will be available already with the launch of the conference! Clearly, the advantage of this procedure is the highest quality of the conference proceedings, namely peer reviewed scientific publications. Already before listening to the presentation or discussing the poster with the author, the participant of the conference will get exposed to the scientific topic, which makes him/her able to better understand the background. This opportunity opens the doors for scientific exchange with the author at its best. The educational aspects of top notch scientific discussions are based on understanding of the topics and competence in communicating the questions and answers. As time slots for oral or poster presentations at conferences are very limited the message transfer has to be well prepared between the peers, i.e. the author of the contribution and the reader of the manuscript. We are aware that some aspects speak against this procedure. The most important argument is that the latest results will not be reported in the paper. We, however, trust that none of the conference participants will be unhappy seeing latest results of a research work in the conference presentation only. Moreover, a scientifically founded discussion might even trigger optimization of the latest results and publication in a follow-up communication. Therefore we are happy to put at disposition to all participants of the EuroCVD20 conference 49 peer reviewed full papers that have been published either in pss(a) or pss(c). We, the co-editors of the EuroCVD20 conference proceedings, wish all readers of the collected papers insight, understanding, fun and pride. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]