Abstract In this study, a surface failure analysis was performed on an aluminum chromium nitride (AlCrN) coating formed on a tungsten carbide (WC) substrate used in a glass-molding machine and subjected to oxidation at elevated temperatures. Several pinholes were observed in the coating, with the coating surface exhibiting discoloring. The microstructures, crystalline structures, and elemental compositions of the coating and substrate were observed using scanning electron microscopy, X-ray diffraction analysis, and X-ray fluorescence spectroscopy. In particular, the phenomena occurring near the coating/substrate interface were examined using focused ion beam milling and grazing incidence X-ray diffraction analysis. The pinholes-containing coating area consisted of an oxide, with the composition of the coating being inhomogeneous. Further, voids were present near the substrate/coating interface, with some of the coating components being detected in the substrate as well. It was concluded that the Al/Cr atomic ratio of the AlCrN coating was not constant, owing to the oxidation of the coating at the elevated temperatures.
#2David Kokalj(Technical University of Dortmund)H-Index: 5
Last. Metin Tolan(Technical University of Dortmund)H-Index: 38
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Abstract Friction minimization is an important topic which is pursued in research and industry. In addition to the use of lubricants, friction-reducing oxide phases can be utilized which occur during. These oxides are called Magneli phases and especially vanadium oxides exhibit good friction reducing properties. Thereby, the lubrication effect can be traced back to oxygen deficiencies. AlCrN thin films are being used as coatings for tools which have to withstand high temperatures. A further impr...
Abstract Transition metal nitrides, such as AlCrN and TiVN, have been used as protective hard coatings due to their excellent tribological properties. In this study, nanostructured AlCrN/TiVN multilayered coatings were deposited periodically by cathodic-arc evaporation (CAE). During the coating process of AlCrN/TiVN, TiN was deposited as an interlayer to enhance adhesion strength between the coating and substrate. The cathode current of both AlCr and TiV alloy targets was controlled to produce h...
Last. Ivi Smid(PSU: Pennsylvania State University)H-Index: 8
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Abstract The impressive history of hardmetals starts with the search for a proper and cheaper material for drawing dies for the drawing of non-sag tungsten (NS-W) after the First World War. The OSRAM R&D group tried to reduce the brittleness of pure WC by adding nickel at first and soon thereafter cobalt, which was utterly successful. Hence, a project aimed to find the solution to a specific problem can unexpectedly lead to a much more important application: The classical hardmetal was born at t...
Last. Dierk Raabe(MPG: Max Planck Society)H-Index: 134
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Microstructural and compositional changes in TiAlN/CrN multilayered films occurring at temperatures up to 1000 °C were studied at different length scales by a combination of atom probe tomography, transmission electron microscopy and X-ray diffraction. We observe the onset of decomposition of the multilayer structure at 700 °C via the mechanism of interface-directed spinodal decomposition of TiAlN layers, where Al atoms preferentially move toward the nearest interface and segregate there. The in...
Last. Zhao Jun(SDU: Shandong University)H-Index: 9
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Abstract Four nitride coatings, TiN, TiAlN, AlTiN and CrAlN were deposited on YG6 (WC + 6 wt.% Co) cemented carbide by cathodic arc-evaporation technique. The friction and wear properties were investigated and compared using ball-on-disc method at high speed with SiC ball as a counter material. The tests were evaluated by scanning electron microscopy, X-ray diffractometer, energy dispersive X-ray, micro hardness tester and an optical profilometer. The results showed that TiN and TiAlN coatings p...
Last. Frédéric Leroy(CNRS: Centre national de la recherche scientifique)H-Index: 19
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Abstract Nanoscience and nanotechnology are tremendously increasing fields of research that aim at producing, characterizing and understanding nanoobjects and assemblies of nanoobjects. Their new physical or chemical properties, which arise from confinement effects, intimately depend on their morphological properties, i.e. their shapes, their sizes and their spatial organization. This calls for dedicated morphological characterization tools, among which is the Grazing Incidence Small Angle X-Ray...
Last. Sam Zhang(NTU: Nanyang Technological University)H-Index: 70
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Abstract In this paper, four kinds of hard coatings, TiN, CrN, TiAlN and CrAlN (with Al/Ti or Al/Cr atomic ratio around 1:1), were deposited on stainless steel substrates by a lateral rotating cathode arc technique. The as-deposited coatings were annealed in ambient atmosphere at different temperatures (500–1000 °C) for 1 h. The evolution of chemical composition, microstructure, and microhardness of these coatings after annealing at different temperatures was systematically analyzed by energy di...
Glass molding is as an effective approach to produce precision micro optical elements with complex shapes at high production efficiency. Since glass is deformed at a high temperature where the mechanical and optical properties depend strongly on temperature, modeling the heat transfer and high-temperature deformation behavior of glass is an important issue. In this paper, a two-step pressing process is proposed according to the non-linear thermal expansion characteristics of glass. Heat transfer...
#1L. Wang(U of W: University of Windsor)H-Index: 8
#2Xueyuan Nie(U of W: University of Windsor)H-Index: 34
Last. Allan Matthews(University of Sheffield)H-Index: 82
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Abstract In this research, CrAlN and TiN coatings were deposited on AISI M2 tool steel substrate test coupons and on industrial punch tools by electron beam plasma-assisted physical vapour deposition (EB-PAPVD). The microstructure and morphology of the coatings were investigated by XRD, XPS, TEM, and SEM with EDX. Pin-on-disc tribotests were conducted on the coatings against AISI 52100 steel counterface material in order to investigate their wear performance, with particular emphasis on the mate...
Last. José F. Marco(CSIC: Spanish National Research Council)H-Index: 31
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Abstract In this work, we have studied the influence of the coating design and composition on the oxidation behavior of Al x Cr 1− x N ( x = 0.70) coatings. In particular, we have studied the effect brought about by the deposition of an additional subsurface titanium nitride barrier layer as well as by the doping of the AlCrN-based coatings by tungsten, boron and silicon. The coatings studied have been deposited using the cathodic arc vacuum (CAV) technique. The multilayered AlCrN/TiN coatings w...
Last. Feng Gong(SZU: Shenzhen University)H-Index: 11
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In the glass molding process, the sticking reaction and fatigue wear between the glass and mold hinder the service life and functional application of the mold at the elevated temperature. To improve the chemical inertness and anti-friction properties of the mold, an amorphous carbon coating was synthesized on the tungsten carbide-cobalt (WC–8Co) substrate by magnetron sputtering. The friction behavior between the glass and carbon coating has a significant influence on the functional protection a...
Last. Naohiko Sugita(UTokyo: University of Tokyo)H-Index: 22
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Abstract In gear skiving, tool wear is one of the primary issues owing to the large thermomechanical cutting load. However, the effective rake angle and depth-of-cut can vary continuously throughout a single cut, leading to a complex uncut chip geometry that significantly hinders the understanding of the cutting characteristics and adds further difficulty to the prediction of tool wear. This study proposes a parametric modeling method for calculating the uncut chip geometry for each cutting pass...
#2Y.L. Su(NCKU: National Cheng Kung University)H-Index: 1
Last. C.M. Wu(NCKU: National Cheng Kung University)H-Index: 1
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Abstract TaNbSiZrCr high entropy alloy (HEA) coatings were deposited on WC substrates using a radio frequency (RF) unbalanced magnetron sputtering system. To explore the effects of nitrogen addition on the coating properties, the coatings were deposited with various nitrogen-to-argon ratios RNx (where x = N2/Ar and lies in the range of 0– 0.5). Furthermore, to examine the effects of heat treatment, half of the coatings were retained in an as-deposited condition, while the remainder were annealed...
#1Feng Guo(USTL: University of Science and Technology, Liaoning)H-Index: 2
#2Xinfang Huang(USTL: University of Science and Technology, Liaoning)H-Index: 4
Last. Qiang Chen(Southwest Wisconsin Technical College)H-Index: 17
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Abstract A microstructure and age-hardening investigation was performed on a chromium nitride and tungsten nitride (CrWN) transition metal nitride coating for optical glass molds using electron microscopy and nano-indentation. The as-deposited coating had a non-uniformly distributed coherent solid solution matrix causing limited strengthening and unsatisfactory mechanical performance. Annealing of the coating induced spinodal decomposition of supersaturated solid solution and promoted diffusion ...
Last. Feng Gong(SZU: Shenzhen University)H-Index: 11
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Abstract The CrxWyNz coatings were synthesized on the cemented carbide (WC-8Co) by plasma-enhanced magnetron sputtering (PEMS). The detailed glass cylinder compression was tested for the molding performance of the coated molds in the precision glass molding machine (PGMM). This work examined the surface morphology evolution, elemental compositions and mechanical properties of the CrxWyNz coatings by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS)...
#1Yung-I Chen(NTOU: National Taiwan Ocean University)H-Index: 12
#2Yi-En Ke(NTOU: National Taiwan Ocean University)H-Index: 2
Last. Li-Chun Chang(MCUT: Ming Chi University of Technology)H-Index: 12
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Abstract Glass molding is widely used for manufacturing high-precision optical elements. Nitride coatings are recommended as protective coatings on glass molding dies. In a die-fixed glass molding system, the molding dies undergo rapid thermal shocks. In this study, near-amorphous Cr–Si–N, Ta–Si–N, and Zr–Si–N coatings with a Si concentration of >14 at.% were prepared. The feasibility of these coatings in the glass molding process was evaluated through rapid thermal cycling annealing in a 15-ppm...
#2Byeong-Seo Son(PNU: Pusan National University)H-Index: 1
Last. Heesoo Lee(PNU: Pusan National University)H-Index: 19
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Abstract A surface analysis was performed on an aluminum chromium nitride (AlCrN) coating formed on a tungsten carbide (WC) substrate subjected to short-term (in minutes) oxidation at an elevated temperature (900 °C) using focused ion beam (FIB), X-ray photoelectron spectroscopy (XPS), grazing incidence X-ray diffraction (GI-XRD), and laser-induced breakdown spectroscopy (LIBS). To separately analyze a coating with a thickness of several micrometers, the GI-XRD method was used. For cross-section...
Abstract The CrWN glass molding coating was synthesized by plasma enhanced magnetron sputtering (PEMS). The effect of annealing environment (e.g., vacuum, N2 and Air) on the microstructure and mechanical property of as-deposited coating was investigated by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscope (AFM) and nanoindentation tests. Results showed that the as-deposited coating exhibited dense columnar structure c...
