Filters

2013 - 20163
Reset filters

Settings

Has files: falseSubject: Boron nitride

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Article
    Citation - WoS: 2
    Performance of Boron Nitride Coated Tools and Dies
    (Univ Maribor, Fac Mechanical Engineering, 2013) Kaftanoglu, B.; Dokmetas, N.
    Boron nitride (BN) has been utilized as a significant coating material for cutting tool applications due to its excellent mechanical and chemical properties. Cutting tools, molds and machine parts are coated with BN with the coating system using a sputtering technology - a physical vapour deposition (PVD) process. Design and manufacture of the equipment is made locally. Physical, mechanical and tribological properties such as thickness, friction coefficient, wear, and adhesion are measured by using calotest, tribometer, profilometer, micro and macro scratch test, and nanohardness devices. The results of characterization of the coatings show that wear resistance and hardness increase and BN coatings provide increased efficiency by creating a value-added manufacturing. In this case, the use of BN-coated tools in machining is expected to be one of the best solutions. (C) 2013 PEI, University of Maribor. All rights reserved.
  • Thumbnail Image
    Article
    Citation - Scopus: 2
    An Environmentally Friendly Method of Cutting and Forming of Materials by Boron Nitride Coated Tools
    (Inderscience Publishers, 2014) Kaftanoǧlu,B.; Dökmetaş,N.
    To decrease the undesirable effects on global warming and environmental pollution, manufacturing techniques should aim to use less energy, generate less pollution to the environment and aim at higher performance in shaping and cutting materials. In this paper, a new coating technique is presented for cutting and forming tools so that they can withstand higher temperatures, preserve their surface quality and cutting edge longer and require minimum quantity of lubrication (MQL) and achieve a longer life. It is known that coolants used in manufacturing cause environmental problems and their processing raises the manufacturing cost. Therefore, MQL or dry cutting is preferred if the tool material can withstand the high temperatures. A new technology of boron nitride (BN) coating using a physical vapour deposition (PVD) system is developed. BN coatings are applied on cutting tools and forming dies. Experiments and industrial applications show an increase in tool life. MQL and manufacturing at higher temperatures can be used due to the stability of BN. Copyright © 2014 Inderscience Enterprises Ltd.
  • Thumbnail Image
    Article
    Citation - WoS: 12
    Citation - Scopus: 14
    Coating of Titanium Implants With Boron Nitride by Rf-Magnetron Sputtering
    (indian Acad Sciences, 2016) Gokmenoglu, Ceren; Ozmeric, Nurdan; Cakal, Gaye; Dokmetas, Nihan; Ergene, Cansu; Kaftanoglu, Bilgin
    Surface modification is necessary for titanium implants since it is unable to induce bone apposition. The beneficial effects of boron on bone formation, composition and physical properties make it suitable as a coating material. In the present study, surface properties of boron nitride (BN) coating on titanium implants were evaluated. Twenty-four implants and 12 abutments were coated with BN by RF-magnetron sputtering system. ATR-FTIR measurements were conducted to assess surface chemistry and morphology of BN-coated implants. Adhesion tests were performed by CSM nanoscratch test device to determine adhesion of BN to titanium surface. Surface profilometry and atomic force microscopy (AFM) was used to evaluate surface roughness. Mean roughness values were calculated. Contact angle measurements were done for evaluation of wettability. Surface characterization of coated implants was repeated after RF power of the system was increased and voltage values were changed to evaluate if these settings have an impact on coating quality. Three different voltage values were used for this purpose. Hexagonal-BN was determined in FTIR spectra. RF-coating technique provided adequate adherence of BN coatings to the titanium surface. A uniform BN coating layer was formed on the titanium implants with no deformation on the titanium surface. Similar roughness values were maintained after BN coating procedure. Before coating, the contact angles of the implants were in between 63(ay) and 79(ay), whereas BN coated implants' contact angles ranged between 46(ay) and 67(ay). BN-coated implant surfaces still have hydrophilic characteristics. The change in voltage values seemed to affect the surface coating characteristics. Especially, the phase of the BN coating was different when different voltages were used. According to our results, BN coating can be sufficiently performed on pretreated implant surfaces and the characteristics of BN coated surfaces can be changed with the change in parameters of RF-magnetron sputtering system.