• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.298.2-298.2
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• 2016

가공이 까다로운 소재를 가공하기 위한 공구에 적용하기 위해서 Al의 함량이 높은 AlTiN 소재가 개발되어 적용되고 있으며, 이 소재는 공구의 수명향상을 위한 표면처리 소재로 각광을 받고 있다. 본 연구에서는 음극 아크 증착 시 거대입자가 박막에 증착되어 결함을 만들기 때문에 그 밀도를 낮추기 위해서 음극 아크 증착을 이용하여 공정 변화에 따른 AlTiN 박막의 표면형상을 관찰하고 특성을 평가하였다. 또한 빗각 증착을 적용하여 제작한 AlTiN 박막의 특성을 평가하였다. Al-25 at.%Ti 합금타겟을 음극 아크 소스에 장착하여 AlTiN 박막을 코팅하였다. 시편은 스테인리스 강판(SUS304)과 초경(tungsten carbide; WC)을 사용하였다. 음극 아크 소스에 인가되는 전류가 낮을수록 AlTiN 박막 표면에 거대입자의 밀도가 낮아졌으며, 기판 전압과 공정압력이 높을수록 AlTiN 박막의 표면에 존재하는 거대입자의 밀도가 낮아지는 경향을 보였다. 이를 통하여 거대입자밀도를 낮추는 기초공정을 도출하였다. AlTiN 박막 제작 시 빗각을 적용한 결과 $60^{\circ}$의 빗각을 적용한 다층 박막에서 약 33 GPa의 경도를 보였다. 본 연구를 통해 음극 아크 증착을 이용하여 거대입자의 밀도가 낮은 박막을 제작할 수 있는 공정을 도출하였고, 빗각증착을 적용하면 경도가 향상되는 결과를 확인하였다. 이를 통해 절삭공구 등과 같이 고경도의 코팅물성 유지를 위한 코팅분야에 응용이 가능할 것으로 판단된다.

• 한국표면공학회지
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• 제42권2호
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• pp.73-78
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• 2009

Quinary Ti-Al-Si-C-N films were successfully synthesized on SUS 304 substrates and Si wafers by a hybrid coating system combining an arc ion plating technique and a DC reactive magnetron sputtering technique. In this work, the effect of Si content on the microstructure and mechanical properties of Ti-Al-C-N films were systematically investigated. It was revealed that the microstructure of Ti-Al-Si-C-N coatings changed from a columnar to a nano-composite by the Si addition. Due to the nanocomposite microstructure of Ti-Al-Si-C-N coatings, the microhardness of The Ti-Al-Si-C-N coatings significantly increased up to 56 GPa. In addition the average friction coefficients of Ti-Al-Si-C-N coatings were remarkably decreased with Si addition. Therefore, Ti-Al-Si-C-N coatings can be applicable as next-generation hard-coating materials due to their improved hybrid mechanical properties.

• 한국분말재료학회지
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• 제27권5호
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• pp.406-413
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• 2020

Ti_0.5Al_0.5N/CrN nano-multilayers, which are known to exhibit excellent wear resistances, were prepared using the unbalanced magnetron sputter for various periods of 2-7 nm. Ti_0.5Al_0.5N and CrN comprised a cubic structure in a single layer with different lattice parameters; however, Ti_0.5Al_0.5N/CrN exhibited a cubic structure with the same lattice parameters that formed the superlattice in the nano-multilayers. The Ti_0.5Al_0.5/CrN multilayer with a period of 5.0 nm exceeded the hardness of the Ti_0.5Al_0.5N/CrN single layer, attaining a value of 36 GPa. According to the low-angle X-ray diffraction, the Ti_0.5Al_0.5N/CrN multilayer maintained its as-coated structure up to 700℃ and exhibited a hardness of 32 GPa. The thickness of the oxidation layer of the Ti_0.5Al_0.5N/CrN multilayered coating was less than 25% of that of the single layers. Thus, the Ti_0.5Al_0.5N/CrN multilayered coating was superior in terms of hardness and oxidation resistance as compared to its constituent single layers.

• 한국세라믹학회지
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• 제34권5호
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• pp.512-518
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• 1997

The high temperature oxidation behaviors of titanium nitride films prepared by PACVD technique were studied in the temperature range of from 50$0^{\circ}C$ to 80$0^{\circ}C$ under air atmosphere. Ti0.88Al0.12N film, which showed the excellent microhardness from the previous work, was investigated on its oxidation resistance compared with pure TiN film. Ti-Al-N film showed superior oxidation resistance up to $700^{\circ}C$, whereas TiN film was fast oxidized into rutile TiO2 crystallites from at 50$0^{\circ}C$. It was found that an amorphous layer having AlxTiyOz formula was formed on the surface region due to outward diffusion of Al ions at the initial stage of oxidation. The amorphous oxide layer played a role as a barrier against oxygen diffusion, protected the remained nitride layer from further oxidation, and thus, resulted in the high oxidation resistive characteristics of Ti-Al-N film.

• 열처리공학회지
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• 제12권3호
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• pp.199-205
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• 1999

The quaternary Ti-Al-V-N films have been grown on glass substrates by reactive dc and rf magnetron sputter deposition from a Ti-6Al-4V target in mixed Ar-$N_2$ discharges. The Ti-Al-V-N films were investigated by means of X-ray diffraction(XRD), electron probe microanalysis(EPMA) and scratch tester. Both XRD and EPMA results indicated that the Ti-Al-V-N films were of single B1 NaCl phase having columnar structure with the (111) preferred orientation. Scratch tester results showed that the adhesion strength of Ti-Al-V-N films which treated with substrate heating and vacuum annealing was superior to that of as-deposited film. The good adhesion strength was also achieved in the double-layer structure of Ti-Al-V-N/Ti-Al-V/Glass.

• 열처리공학회지
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• 제8권3호
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• pp.187-196
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• 1995

TiN and AlN are ceramic materials with mechanical and chemical properties for use in structural applications at elevated temperature. The purpose of this research is to develop the technology for the synthesis of (Ti, Al)N power, which shows simultancously the excellent properties of TiN and AlN, from the mixed powder($Ti_{0.25}Al_{0.75}$, $Ti_{0.5}Al_{0.5}$ and $Ti_{0.75}Al_{0.25}$) by the direct nitriding method. The effects of variables such as temperature, mixing ratio of Al to Ti in raw material were investigated. The(Ti, Al)N powder can be easily synthesized from the mixed powder by the direct nitriding method. Among the mixed powdres, the nitriding behavior decreased with increasing the ratio of Al to Ti. This behavior is well explained by the nitriding mechanism presented in this research.

• 열처리공학회지
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• 제13권6호
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• pp.398-404
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• 2000

The Ti-Al-V-N films have been deposited on various substrates by d.c and r.f reactive magnetron sputtering from a Ti-6Al-4V alloy target in mixed $Ar-N_2$ discharges. The films were investigated by means of XRD, AES, SEM/EDX, microhardness, TG and scratch test. The XRD and SEM results indicated that the films were of single B1 NaCl phase having dense columnar structure with the (111) preferred orientation. The composition of Ti-Al-V-N film was the Ti-7.1Al-4.3V-N(wt%) films. Adhesion and microhardness of Ti-Al-V-N films deposited by r.f magnetron sputtering method were better than those deposited by d.c magnetron sputtering method. The anti-oxidation properties of Ti-Al-V-N films were also superior to that of Ti-N film deposited by the same deposition conditions.

• 열처리공학회지
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• 제19권4호
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• pp.225-229
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• 2006

TiAlN coatings are available in various industry fields as a wear resistant coating for high-speed machining, due to its high hardness, excellent oxidation and corrosion resistance. The corrosion resistance of TiAlN multilayer coatings is better than that of single TiN coatings. Most of TiAlN coated layers were formed by heat treatment of coating layers with a non-stoichiometric $Ti_xAl_{1-x}N$. In this study, TiAlN coated layer was prepared by R.F magnetron sputtering and investigated the thermal behavior for heat treatment at various temperature in tube furnace. The formation of large particles with porous microstructure and phase change from HCP to FCC were observed on coated layer during heat treatment over $850^{\circ}C$ and it reduced the corrosion resistance of coated TiAlN layers.

• 한국추진공학회지
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• 제5권1호
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• pp.49-59
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• 2001

경사기능재료(FGM)는 일반적으로 세라믹스나 금속과 같은 서로 다른 재료로 이루어져 있다. FGM의 성질은 조성구배, 미세조직, 기공율에 의해 변화가 일어난다. 본 연구에서는 입방체 AlN/Al-$Al_3$Ti FGM은 분말야금공정으로 제조하였고 그 특성을 관찰하였다. Al에 서로 다른 Mg와 Ti 분말을 steel 몰드에 조성구배를 폭넓게 하여 적층, 혼합하였다. 소결온도와 Mg의 양을 점점 증가시킴으로써 형성된 AlN의 양도 더 증가하였다. AlN과 $Al_3$Ti는 조성구배를 XRD 분석, 광학현미경으로 조직을 관찰하였으며 미소경도시험을 행하였다.

• 한국표면공학회지
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• 제54권5호
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• pp.230-237
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• 2021

In this study, the influence of silicon contents on the microstructure, mechanical and tribological properties of Ti-Al-Si-N coatings were systematically investigated for application of cutting tools. The composition of the Ti-Al-Si-N coatings were controlled by different combinations of TiAl₂ and Ti₄Si composite target powers using an arc ion plating technique in a reactive gas mixture of high purity Ar and N₂ during depositions. Ti-Al-Si-N films were nanocomposite consisting of nanosized (Ti,Al,Si)N crystallites embedded in an amorphous Si₃N₄/SiO₂ matrix. The instrumental analyses revealed that the synthesized Ti-Al-Si-N film with Si content of 5.63 at.% was a nanocomposites consisting of nano-sized crystallites (5-7 nm in dia.) and a three dimensional thin layer of amorphous Si₃N₄ phase. The hardness of the Ti-Al-Si-N coatings also exhibited the maximum hardness value of about 47 GPa at a silicon content of ~5.63 at.% due to the microstructural change to a nanocomposite as well as the solid-solution hardening. The coating has a low friction coefficient of 0.55 at room temperature against an Inconel alloy ball. These excellent mechanical and tribological properties of the Ti-Al-Si-N coatings could help to improve the performance of machining and cutting tool applications.