• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.106-109
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• 2011

We investigated the etching characteristics of titanium nitride (TiN) thin film in $BCl_3$/Ar inductively coupled plasma. The etching parameters were the gas mixing ratio, radio frequency (RF) power, direct current (DC)-bias voltages and process pressures. The standard conditions were as follows: total flow rate = 20 sccm, RF power = 500 W, DC-bias voltage = -100 V, substrate temperature = $40^{\circ}C$, and process pressure = 15 mTorr. The maximum etch rate of TiN thin film and the selectivity of TiN to $Al_2O_3$ thin film were 54 nm/min and 0.79. The results of X-ray photoelectron spectroscopy showed no accumulation of etch byproducts from the etched surface of TiN thin film. The TiN film etch was dominated by the chemical etching with assistance by Ar sputtering in reactive ion etching mechanism, based on the experimental results.

• Advances in biomechanics and applications
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• v.1 no.1
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• pp.23-40
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• 2014

This paper examines the blood chamber of a left ventricular assist device (LVAD) under static loading conditions and standard operating temperatures. The LVAD's walls are made of a temperature-sensitive polymer (ChronoFlex C 55D) and are covered with a titanium nitride (TiN) nano-coating (deposited by laser ablation) to improve their haemocompatibility. A loss of cohesion may be observed near the coating-substrate boundary. Therefore, a micro-scale stress-strain analysis of the multilayered blood chamber was conducted with FE (finite element) code. The multi-scale model included a macro-model of the LVAD's blood chamber and a micro-model of the TiN coating. The theories of non-linear elasticity and elasto-plasticity were applied. The formulated problems were solved with a finite element method. The micro-scale problem was solved for a representative volume element (RVE). This micro-model accounted for the residual stress, a material model of the TiN coating, the stress results under loading pressures, the thickness of the TiN coating and the wave parameters of the TiN surface. The numerical results (displacements and strains) were experimentally validated using digital image correlation (DIC) during static blood pressure deformations. The maximum strain and stress were determined at static pressure steps in a macro-scale FE simulation. The strain and stress were also computed at the same loading conditions in a micro-scale FE simulation.

• Journal of the Korean Ceramic Society
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• v.27 no.7
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• pp.916-924
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• 1990

The preparatin of the fine TiN powders by reduction-nitridation of TiCl3-Al-N2 system was attempted in the temperature range from 350$^{\circ}$to 100$0^{\circ}C$. The formation mechanism and kinetics of TiN were examined, and the resultant TiN powder was characterized by means of XRD, PSA and SEM-EPMA methods. TiN was formed at temperatrue higher than $600^{\circ}C$. As an intermediate phase, AlTi was obtained. The apparent activation energy for the formation of TiN was approximately 4.2kcal/mole(600$^{\circ}$~90$0^{\circ}C$). The crystallite size and lattice constnat of TiN powder obtained in the temperature range from 600$^{\circ}$to 100$0^{\circ}C$ for 2h at the Al/TiCl3 molar ratio of 1.0 were 160~255A and 4.231~4.239A, respectively. According to PSA measurement, the mean particle size ranged from 14.0 to 14.8${\mu}{\textrm}{m}$.

• Tribology and Lubricants
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• v.4 no.2
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• pp.36-43
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• 1988

Titanium carbide(TiC) and titanium nitride(TiN) flims were deposited on $Si_3N_4$-TiC composite cutting tools by chemical vapor deposition(CVD) using $TiCl_4-CH_4-H_2$ and $TiCl_4-H_2-N_2$ gas mixtures, respectively. The nonmetal to metal ratio of deposit increases with increasing $m_{C/Ti}$(mole ratio of CH$_4$ to TiCl$_4$ in the input) for TiC coatings and $m_{N/Ti}$(mole ratio of N$_2$ to TiCl$_4$ in the input) for TiN coatings. The nearly stoiahiometric films could be obtained under the deposition condition of $m_{C/Ti}$ between 1.15 and 1.61 for TiC, and that of $m_{N/Ti}$ between 25 and 28 for TiN. Also maximum microhardness of the coatings can be obtained in these ranges. The interfacial region of TiC coatings on $Si_3N_4$-TiC ceramics is wider than that of TiN coatings according to Auger depth profile analysis, which indicates good interfacial bonding for TiC. Experimental results show that TiC coatings have an randomly equiaxed structure and Columnar structure with(220) preferred orientation can be obtained for TiN coatings. And, multilayer coatings have a dense and equiaxed structure.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.5
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• pp.373-379
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• 2020

In this study, TiN-coated cBN (cubic-structure boron nitride) powders were successfully synthesized by a sol-gel method using titanium (IV) isopropoxide (TTIP) and by controlling the heat treatment conditions. After the sol-gel process, amorphous nano-sized TiO_x was uniformly coated on the surface of cBN powder particles. The obtained TiO_x-coated cBN powders were heated at 1,000~1,300℃ for 1 or 6 h in a flow of 95%N₂-5%H₂ mixed gas. With increasing temperature, the chemical composition of the TiO_x coating layer changed in the order of TiO₂→Ti₆O₁₁→Ti₄O₇→TiN due to reduction of the Ti ions. The TiN coating layer was observable in the samples heated at 1,200℃ and appeared as the main phase in the sample heated at 1,300℃. The resulting thickness of the TiN coating layer of the sample heated at 1,300℃ was approximately 45~50 nm.

• Steel and Composite Structures
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• v.23 no.2
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• pp.153-160
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• 2017

It is extremely important to be aware of the ballistic performances of engineering materials in order to be able to choose the lightest armor providing full ballistic protection in civil and military applications. Therefore, ballistic tests are an important part of armor design process. In this study, ballistic performance of plates made of carbon steel and cold worked tool steel against 7.62 mm AP (armor-piercing) bullets was examined experimentally and numerically in accordance with NIJ standards. Samples in different sizes were prepared to demonstrate the effect of target thickness on ballistic performance. Some of these samples were coated with titanium nitride using physical vapor deposition (PVD) method. After examining all successful and unsuccessful samples at macro and micro levels, factors affecting ballistic performance were determined. Explicit non-linear analyses were made using Ls-Dyna software in order to confirm physical ballistic test results. It was observed that the ballistic features of steel plates used in simulations comply with actual physical test results.

• Journal of the Korean institute of surface engineering
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• v.24 no.4
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• pp.196-205
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• 1991

Multi-level thin films are very important in ULSI applications because of their high electromigration resistance. This study presents the effects of titanium, titanium nitride and titanium tungsten underlayers of the stability of multi-aluminum thin films during isothermal annealing. High purity Al(99.999%) films have been electron-beam evaporated on Ti, TiN, TiW films formed on SiO2/Si (P-type(100))-wafer substrates by RF-sputtering in Ar gas ambient. The hillock growth was increased with annealing temperatures. Growth of hillocks was observed during isothermal annealing of the thin films by scanning electron microscopy. The hillock growth was believed to appear due to the recrystallization process driven by stress relaxation during isothermal annealing. Thermomigration damage was also presented in thin films by grain boundary grooving processes. It is shown that underlayers of Al/TiN/SiO2, Al/TiW/SiO2 thin films are preferrable to Al/SiO2 thin film metallization.

• The korean journal of orthodontics
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• v.51 no.4
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• pp.270-281
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• 2021

Objective: The aim of this in vitro study was to evaluate the changes in friction between orthodontic brackets and archwires coated with aluminum oxide (Al₂O₃), titanium nitride (TiN), or chromium nitride (CrN). In addition, the resistance of the coatings to intraoral conditions was evaluated. Methods: Stainless steel canine brackets, 0.016-inch round nickel-titanium archwires, and 0.019 × 0.025-inch stainless steel archwires were coated with Al₂O₃, TiN, and CrN using radio frequency magnetron sputtering. The coated materials were examined using scanning electron microscopy, an X-ray diffractometer, atomic force microscopy, and surface profilometry. In addition, the samples were subjected to thermal cycling and in vitro brushing tests, and the effects of the simulated intraoral conditions on the coating structure were evaluated. Results: Coating of the metal bracket as well as nickel-titanium archwire with Al₂O₃ reduced the coefficients of friction (CoFs) for the bracket-archwire combination (p < 0.01). When the bracket and stainless steel archwire were coated with Al₂O₃ and TiN, the CoFs were significantly lower (0.207 and 0.372, respectively) than that recorded when this bracket-archwire combination was left uncoated (0.552; p < 0.01). The friction, thermal, and brushing tests did not deteriorate the overall quality of the Al₂O₃ coatings; however, some small areas of peeling were evident for the TiN coatings, whereas comparatively larger areas of peeling were observed for the CrN coatings. Conclusions: Our findings suggest that the CoFs for metal bracket-archwire combinations used in orthodontic treatment can be decreased by coating with Al₂O₃ and TiN thin films.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.11a
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• pp.37-37
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• 2001

TiN coatings were applied for VarIOUS application fields, because of a good wear-resistance and a high hardness. Typically, TiN thin films show the hardness of 25GPa and friction coefficient of 0.6. However, in many field, one is looking for a more improved tool which has low friction coefficient and high wear resistance. The main motivation of this study is to characterize the influence of copper dopant content on TiN thin films. Ti-Cu-N thin films were deposited onto D2 steel substrates by PVD processing with various magnetron current densities (Cu contents). In this work, we synthesized titanium nitride films similar with reported typical titanium nitride films and synthesized Ti-Cu-N thin films with the addition of elemental copper which is measured improved hardness more than pure TiN films with copper content variables. This films has preferred oriented films of (111) direction. In addition, It was found that there is a strong correlation between content of various metal and film characteristics such as preferred orientation, grain size, hardness and friction coefficient and so, in future study, improved mechanical properties of TiN films can be controlled by change in target current density. The Ti-Cu-N film will show apparent hardness improvement and mechanical properties enhancement, when doping element is added onto TiN thin films. Film structure, chemical composition, mechanical properties were investigated by means of X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy(EDS), wear resistance tester and nanohardness tester.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.5
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• pp.675-686
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• 2007

Statement of problem: Titanium nitride(TiN) coatings are the most general and popular coating method and used to improve the properties of metallic surface for industrial purposes. When TiN coating applied to the abutment screw, frictional resistance would be reduced, as a results, the greater preload and prevention of the screw loosening could be expected. Purpose: The purpose of this study was to investigate mechanical properties of TiN coated film of various coating thickness on the titanium alloy surface and to evaluate proper coating thickness. Material and method: 95 Titanium alloy (Ti-6Al-4V) discs of 15 mm in diameter and 3 mm in thickness were prepared for TiN coating and divided into 7 groups in this study. Acceding to coating deposition time (CDT) with TiN by using Arc ion plating, were divided into 7 groups : Group A (CDT 30min), Group B (CDT 60min), Group C (CDT 90min), Group D (CDT 120min), Group E (CDT 150min), Group F(CDT 180min) and Group G (no CDT) as a control group. TiN coating surface was observed with Atomic Force Microscope(AFM), field emission scanning electron microscopy(FE-SEM) and examined with scratch tester, wear tester. Result: 1. Coating thickness fir each coated group was increased in proportion to coating deposition time. 2. Surface of all coated groups except Group A was homogeneous and smooth. However, surface of none coated Group G had scratch. 3. Adhesion strength for each coated group was increased in proportion to coating deposition time. 4. Wear resistance for each coated group was increased in proportion to coating deposition time. 5. Surface roughness in Group A, B, C was increased in proportion to coating deposition time. But, surface roughness in Group D, E, F was showed decreased tendency in proportion to coating deposition time. Conclusion: According to coating deposition time, mechanical properties of TiN coated film were changed. It was considered that 120 minutes coating deposition time ($1.32{\mu}m$ in coating thickness) is necessary.