• KSTLE International Journal
• /
• 제3권1호
• /
• pp.43-48
• /
• 2002

Dry sliding wear and friction test of CrN coaling on two types of aluminum alloy substrates,6061 Al and 7075 Al deposited by arc ion plating, was peformed with a ball-on-disk tribometer. The effects of normal Bead and the mechanical properties of substrate on the friction coefficient and wear-resistance of CrN coating were investigated. The worn surfaces were observed by SEM. The results show that surface micro-hardness of CrN- coated 7075 Al is higher than that of CrN-coated 6061 Al. With an increase in normal lead, wear volume increases, while the friction coefficient decreases. The friction coefficient of CrN-coated 6061 Al is higher than that of CrN-coated 7075 Al, while the wear-resistance of CrN-coated 6061 Al is lower than the CrN-coated 7075 Al's, which indicates that the substrate mechanical properties have strong inf1uences on the friction coefficient and wear of CrN coating. The main wear mechanism was fragments of CrN coating, which were caused by apparent plastic deformation of substrate during wear test.

• 한국표면공학회지
• /
• 제43권6호
• /
• pp.278-282
• /
• 2010

In this research, the friction and wear characteristic behaviors of coating materials of TiAlN and CrAlN were investigated. The wear test was conducted in air and un-lubricated state using the reciprocating friction wear tester. Temperature were 50 and $120^{\circ}C$, and load were 3, 7, and 11 kgf for tests. By comparing the coefficient of friction and observing the wear microstructure, the friction and wear characteristic behaviors of TiAlN and CrAlN coating layers on SKD61 were investigated. The coefficient of friction of CrAlN coating was lower than that of TiAlN at all conditions. Therefore, CrAlN was suggested to be more advantageous coating than TiAlN for the extrusion mold of aluminum.

• 한국표면공학회지
• /
• 제57권1호
• /
• pp.14-21
• /
• 2024

For this study, CrAlN multilayer coatings were deposited on SKD61 substrates using a multi-arc ion plating technique. The structural characteristics of the CrAlN multilayer coatings were evaluated using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Additionally, the adhesion of the coatings was assessed through scratch testing, and the mechanical strength was evaluated using nanoindentation and tribometric tests for frictional properties. The results show that the CrAlN multilayer coatings possess a uniform and dense structure with excellent mechanical strength. Hardness measurements indicated that the CrAlN coatings have high hardness values, and both the coating adhesion and wear resistance were found to be improved compared to CrN. The addition of aluminum is anticipated to contribute to enhanced durability and wear resistance.

• 한국표면공학회지
• /
• 제54권5호
• /
• pp.285-293
• /
• 2021

High-entropy TiAlCrSiN nano-composite coating was designed to improve mold life for high temperature liquid molding. Alloy design, powder fabrication and single alloying target fabrication for the high-entropy nano-composite coating were carried out. Using the single alloying target, an arc ion plating method was applied to prepare a TiAlCrSiN nano-composite coating had a 30 nm TiAlCrSiN layers are deposited layer by layer, and form about 4 ㎛-thickness of multi-layered coating. TiAlCrSiN nano-composite coating had a high hardness of about 39.9 GPa and a low coefficient of friction of less than about 0.47 in a dry environment. In addition, there was no change in the structure of the coating after the dissolution loss test in the molten metal at a temperature of about 1100 degrees.

• 한국재료학회지
• /
• 제14권8호
• /
• pp.558-564
• /
• 2004

In order to improve the low hardness and low wear resistance of Ti-6Al-4V alloy, plasma carburization treatment and CrN film coating were carried out. Effects of the plasma carburization and CrN coating were analyzed and compared with the non-treated alloy by mechanical and creep tests. After plasma carburization and CrN coating treatments, the carburized layer was about 150 ${\mu}m$ in depth and CrN coated layer was about 7.5 ${\mu}m$ in thickness. Hardness value of about $H_{v}$ 402 of the non-treated alloy was improved to $H_{v}$ 1600 and 1390 by plasma carburization and CrN thin film coating, respectively. Stress exponent(n) was decreased from 9.10 in CrN coating specimen to 8.95 in carburized specimen. However, the activation energy(Q) was increased from 242 to 250 kJ/mol. It can be concluded that the static creep deformation for Ti-6Al-4V alloy is controlled by the dislocation climb over the ranges of the experimental conditions.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2000년도 춘계학술대회 논문집
• /
• pp.164-169
• /
• 2000

The remote measurement system(RMS) as a new experimental method is limited in its application to crack measurements at elevated temperatures because of the oxide layer on the specimen surface. Since TiAlN and Cr coating layers have a high resistance to oxidation and wear, this paper proposed a TiAlN and Cr coating technique for specimens to facilitate the measurement of crack growth behavior using RMS. To investigate the effects of the coating layer, tension and fatigue tests were carried out at room temperature and at 538$^{\circ}C$, using specimens of 1Cr-1Mo-0.25V steel. From the experimental results, it was found that the mechanical properties of the TiAlN and Cr coated specimens were similar to those of the substrate. Accordingly, the TiAlN and Cr coated layer had hardly any influence on the fatigue crack propagation.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2007년도 추계학술대회 논문집
• /
• pp.128-129
• /
• 2007

Cr-Al-N, Cr-Si-N 그리고 Cr-Al-Si-N 코팅막을 WC-Co 모재위에 AIP법과 DC 마그네트론 스퍼터링 법을 결합한 하이브리드 시스템을 이용하여 합성하였으며, Si함량에 따른 Cr-Al-Si-N 코팅막의 미세구조, 기계적 특성과 마찰 거동에 관해 비교 연구하였다. Cr-Si-N(${\sim}35GPa$)과 Cr-Al-Si-N(${\sim}55GPa$) 코팅막의 경도값은 CrN(${\sim}23GPa$)과 Cr-Al-N(${\sim}25GPa$) 코팅막과 비교하여 각각 증가하였고, CrN(${\sim}0.50$)과 Cr-Al-N(${\sim}0.84$)의 평균 마찰계수는 Si 함량이 9 at.% 일때, Cr-Si-N(${\sim}0.30$)과 Cr-Al-Si-N(${\sim}0.57$)으로 각각 감소하였다.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2008년도 추계학술대회 초록집
• /
• pp.47-47
• /
• 2008

Cr and AlSi (Si=20 and 66 at.%) target들을 이용하여 Closed-field unbalanced magnetron sputtering (CFUBMS)으로 증착된 주기($\Lambda$)가 2.3 nm에서 8.0nm인 CrN/AlSiN multilayer coatings의 crystal structure, 화학적 조성, 및 기계적 특성을 glow discharge optical emission spectroscopy (GDOES), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS) and nano-indenter 등의 분석장비를 이용하여 분석하였다. 고온안정성을 시험하기 위하여 $800^{\circ}C$와 $1000^{\circ}C$ 공기중 에서 30분 열처리하였다. CrN/AlSiN multilayer coatings의 고온안정성은 Si조성이 증가함에 따라 향상되었다. Si이 18.2 at.%함유된 coating이 가장 우수한 고온안정성을 갖고 있다.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2018년도 춘계학술대회 논문집
• /
• pp.131-131
• /
• 2018

최근 절삭공구산업은 자동차, 항공기, IT, 선박, 에너지 등 첨단산업의 증가로 인해 CGI, CFRP, 내열합금 등 난삭재의 수요가 증가하고 있다. 난삭재는 고내열, 고경도, 초경량 같은 특성을 지니며 우수한 기계적 물성을 갖지만 가공의 어려움이 있어 산업에 적용하는데 한계가 있다. 이러한 한계를 극복하기 위해 개발된 가공기술 중 하드 코팅은 공구코팅비용 대비 공구의 표면경도와 수명을 효율적으로 향상시킬 수 있다고 알려져 있다. 대표적인 하드코팅으로는 AlN계, TiN계 코팅이 있다. 이러한 코팅의 경우 높은 기계적 물성과 우수한 내마모성으로 인해 절삭공구의 성능을 향상시킬 수 있기 때문에, 많은 연구가 진행되고 있으며 절삭공구산업에서 각광받고 있다. 기존 선행연구 결과에 따르면 질화물 코팅의 우수한 물성은 질화물(Nitride) 생성 및 질화 공정에 의한 코팅층의 고밀도화에 의해 나타난다고 알려져 있다. 그 중에서 AlCrN coating은 우수한 내마모성 및 향상된 고온경도를 갖고 있다. AlCrN based coating에 미량의 원소를 첨가하여 기존 AlCrN coating의 기계적 특성을 더욱 향상 시킨 coating은 일반적인 고성능 코팅 대비 공구수명이 길다고 알려져 있으며, 전반적으로 우수한 특성에 의해 전 세계적으로 습식 및 건식 기계 가공 용도로 사용되고 있다. 본 연구에서는 AlCrN based coating에 미량의 원소를 첨가한 coating의 우수한 기계적 특성의 원인을 규명하기 위해 텅스텐카바이드(WC) 기판 위에 아크 이온 플레이팅 장비를 이용하여 AlCrN based coating을 증착 시킨 sample을 분석하였다. 결정구조 및 상 분석을 위해 X선 회절분석(XRD)을 실시하였으며, 미세 구조를 분석하기 위해 전계방출형 주사전자현미경(FE-SEM), 투과 전자현미경(TEM) 분석을 실시하였다. 또한 코팅층의 화학적 성분 분석을 위해 EDX분석을 실시하였으며 기계적 특성 평가를 위해 나노압입시험(Nano-indentation test)을 진행하였다.

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