• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 추계학술대회 논문집
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• pp.123-124
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• 2007

3성분계 Ti-Si-C 코팅은 PECVD 기술에 의해 WC-Co 기판에 합성되었다. 이 연구에서 Ti-Si-C코팅에서의 비정질 silicon carbide 상의 효과는 XRD, XPS, TEM에 의해 분석되었다. TiC 결정의 입자크기는 비정질 silicon carbide의 침투 현상 때문에 Si의 함유량이 증가됨에 따라 감소된다. Ti-Si-C 코팅은 5.2%의 Si함유량에서 나노크기의 nc-TiC결정과 비정질 a-SiC로 이루어져 있고 최고 경도 33GPa와 탄성율 330GPa를 각각 보여주고 있다. 이 수치들은 순수한 TiC(-21GPa, 260Gpa)보다 눈에 띄게 높아졌다.

• 한국세라믹학회지
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• 제36권4호
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• pp.451-458
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• 1999

TiC-Mo2C composites were prepared from Ti-C-Mo system by HPCS which has a great advantage of simulataneous synthesis and sintering In this study physical properties and microstructures of the com-posites were measured and observed to compare the sintering effects of Ni and Co each other : The results showed that the role of 5 wt% Ni in the sintering of the carbide composites was superior to that of 5wt% Co and the optimum content of Mo in the Ti-C-Mo system was 20wt% The carbide composites prepared under these two conditions had the best properties with 1.0% in apparent porosity 97.6% in relative density 19.1GPa in Vickers hardness and 5.3MPa$.$m1/2 in fracture toughness.

• 한국세라믹학회지
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• 제36권4호
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• pp.366-371
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• 1999

The effect of VC addition on the microstructural evolution of Fe-TiC cermet has been investigated. The microstructures of the Fe-TiC varied with the amount of VC addition. The addition of 1wt% VC enhanced the instability of liquid-solid interface ; the dissolving interface showed round shape instead of facetted one which was ascribed to the increase of lattice mismatch between TiC and solid-solution carbide. in the speci-men with 10wt% VC the new set of solid-solution carbide grains of uniform and small size was formed in-side coarse TiC particles by diffusion induced recrystallizatin (DIR). With increasing the heat-treatment time fine recrystallized grains were dispersed homogeneously in the matrix and resulted in the increase in fracture strength.

• 한국표면공학회지
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• 제47권5호
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• pp.252-256
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• 2014

The TiAlCrSiN film was deposited on the WC-20%TiC-10%Co carbide, and its oxidation behavior was examined at $700-1000^{\circ}C$. It displayed relatively good oxidation resistance owing to the formation of $TiO_2$, $Al_2O_3$, $Cr_2O_3$, and $SiO_2$ up to $900^{\circ}C$. However, at $1000^{\circ}C$, the fast oxidation rate and partial oxidation of WC in the substrate led to the formation of the thick, fragile oxide scale.

• 대한화학회지
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• 제57권6호
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• pp.677-683
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• 2013

A theoretical study of the electronic structures of $TiC_{1-x}$ and $Ti_{1-x}W_xC$ (x = 0, 0.25) is presented. The density of states and crystal orbital overlap population calculations were used to interpret variations of elastic properties induced by carbon vacancies and alloying substitutions. Our results show why the introduction of vacancies into TiC reduces bulk moduli, while W substitution at a Ti site increases the elastic modulus. The effect of the point defects on the bonding in TiC is investigated by means of extended Huckel tight-binding band calculations.

• 열처리공학회지
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• 제30권2호
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• pp.43-52
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• 2017

Heat treatment condition for dissolution of the M23C6 carbides in 2.25Cr-1Mo-V-Ti material for thermal power plant tube was investigated using a dilatometer method. 2.25Cr-1Mo-V-Ti material was heat-treated at $900{\sim}1,100^{\circ}C$ for 0, 10, 30 min to find the proper dissolution condition of M23C6 carbides. The phase identification and volume fraction of the carbide were measured by using OM, SEM, EBSD and TEM analysis. Optimal heat treatment condition of M23C6 carbide dissolution was selected by predicting dissolution temperature of carbide using Bs points appeared at dilatometer curve. Experimental results showed that the conditions of carbide dissolution was 900, 1,000, $1,100^{\circ}C$ for 30 min. Eventually, the optimal heat treatment condition for dissolution was 30 min at $1,000^{\circ}C$ considering the minimum coarsening of Austenite grain size.

• 한국재료학회지
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• 제12권10호
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• pp.825-830
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• 2002

The growth rate of solid grains in TiC-XC-2vol% and TiC-XC-30vo1% Ni cermets, where X=Zr, W or Mo, was fitted to an equation of the form $d^3$-$do^3$=Kt. The grain growth behavior during liquid phase sintering at 1673K decreased markedly with addition of $Mo_2$C or WC and increased with addition of ZrC. The contiguity ratio was greater in the alloys with smaller growth rate constant and decreased with increasing Ni content in the $TiC-Mo_2$C-Ni cermet. The grain growth mechanism could be explained by the effect of contiguous grain boundaries in restricting the overall grain growth.

• 한국생산제조학회지
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• 제21권5호
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• pp.848-854
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• 2012

SCM420 steel cutting gear to improve the durability is quenched. When quenching, increases surface hardness, a change of the physical properties and machinability or fall. This study, using a solid carbide hobs skiving hobbing gear cutting finishing. And cutting tool solid carbide TiAlN coating hove when TiAlN coating on the surface of multi-con polishing hob conducted aero lap nano polishing for each cutting. Experimental results conducted aero lap nano coating on the surface polishing tool machinability was excellent. And aero lap nano polishing tool results were reduced 2.5 times the tool wear compared to TiAlN coated tools. Excellent results were 1.42 times longer tool life.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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• pp.313-318
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• 2001

The sliding wear behavior of Plasma-Sprayed Al$_2$O$_3$-TiO$_2$ Coating against Cemented Carbide were Investigated using a pin on disk type tester. The experiment was conducted using Al$_2$O$_3$-TiO$_2$ Coaling as pin material and Cemented Carbide as disk material and different operating conditions, at room temperature under a dry conditions. The results showed that the type B(250kw power) appeared average wear rate Is lowed than type A(80kw power). The specific wear rate of Specimen A1 Increased with normal load. But The specific wear rate of Specimen B1 decreased with normal load. Average wear rate of specimen A3, B3 are lowed than other but the sliding wear mechanism of edge were rough.

• 한국표면공학회지
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• 제24권1호
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• pp.16-16
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• 1991

Generally brittle eta phase produced during TiC deposition has a effect on the TRS (transverse rupture strength ; thoughness). Therefore it is necessary to reduce eta(η), phase for the improvement of tool life. At this experiment some properties (TRS, bonding strength, tool life, eta phase)have been investigated by inserting TiN or TiCN underlayer between TiC layer and substrate. The results obtained were as follows; 1. by inserting underlayer eta phase were decreased and TRS was increased, but the bonding strength was decreased. 2. the diffusion of W, Co from the substrate was hindered by the underlayer. 3. TiC layer with TiCN underlayer had the finsest grain size. 4. by inserting underlayer (TiCN or TiN) the tool life was improved and especially notch and crater wear resistance was greatly improved.