• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.859-860
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• 2006

TiC-$TiB_2$-SiC system was a ternary eutectic, whose eutectic composition was 34TiC-$22TiB_2$-44SiC (mol%). TiC-$TiB_2$-SiC ternary eutectic composite were synthesized by a floating zone method using TiC, $TiB_2$ and SiC powders as starting materials. The TiC-$TiB_2$-SiC eutectic composite showed a lamellar texture. TiC(022), $TiB_2(010)$ and SiC(111) of the eutectic composite were perpendicular to the growth direction. TiC-$TiB_2$-SiC ternary eutectic composite had specific relationship among the crystal planes: TiC[011]//$TiB_2[010]$//SiC[112], TiC(200)//$TiB_2$(001)//SiC(402) and $TiC(1\bar{1}1)$//$TiB_2(101)$//SiC(220).

• 한국산학기술학회논문지
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• 제15권3호
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• pp.1253-1258
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• 2014

CA 이온도금기술에 의한 TiC와 TiN 그리고 TiC/TiN 코팅재를 비교하기 위하여 트라이볼로지 물성을 연구하였다. 실험은 Falex journal V block 시스템을 이용한 터보시험기에서 수행하였다. 코팅재의 마찰과 마모특성은 작용된 하중과 미끄럼 속도에 의하여 다양하게 결정되었다. TiC와 TiN 그리고 TiC/TiN 코팅재는 표면에서 트라이볼로지 특성이 현저하게 증가하였다. 단층코팅에서는 TiC보다 TiN이 좋은 결과를 얻었다. 그러나, TiC/TiN의 다층코팅은 다른 어떤 단층코팅보다 좋은 성능을 보였다. 다층코팅의 성능이 향상된 핵심요소는 TiN층 외부와 강 사이에서 부착이 증가하게된 TiC의 역할 때문이다.

• Tribology and Lubricants
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• 제4권2호
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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.

• 한국세라믹학회지
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• 제31권8호
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• pp.849-860
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• 1994

The microstructural evolution and crystalline phases of this infiltration of Ti+Al liquids in TiC, SiC, TiC+C, and SiC+C preforms have been investigated. As the Ti and Al mixing ratio in Ti+Al infiltrated liquid changes, the newly formed reaction products, which were reacted from the Ti+Al liquid with preforms, consisted of three major phases as Ti3AlC, Al2Ti4C2 or Al4C3. The TiC grain shape was changed to spheroid, when Ti3AlC was formed. In case of Al2Ti4C2 formation, the platelet grain was formed from the original TiC grain. When Al4C3 was formed, nodular or intergranular fine-grained Al4C3 was formed around the TiC grain, while the original TiC grain shape was not changed.

• 한국재료학회지
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• 제25권1호
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• pp.48-53
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• 2015

$TiH_2$ nanopowder was made by high energy ball milling. The milled $TiH_2$ and CNT powders were then simultaneously synthesized and consolidated using pulsed current activated sintering (PCAS) within one minute under an applied pressure of 80 MPa. The milling did not induce any reaction between the constituent powders. Meanwhile, PCAS of the $TiH_2$-CNT mixture produced a Ti-TiC composite according to the reaction ($0.92TiH_2+0.08CNT{\rightarrow}0.84Ti+0.08TiC+0.92H_2$, $0.84TiH_2+0.16CNT{\rightarrow}0.68Ti+0.16TiC+0.84H_2$). Highly dense nanocrystalline Ti-TiC composites with a relative density of up to 99.7% were obtained. The hardness and fracture toughness of the dense Ti-8 mole% TiC and Ti-16 mole% TiC produced by PCAS were also investigated. The hardness of the Ti-8 mole% TiC and Ti-16 mole% TiC composites was higher than that of Ti. The hardness value of the Ti-16 mole% TiC composite was higher than that of the Ti-8 mole% TiC composite without a decrease in fracture toughness.

• 한국세라믹학회지
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• 제40권1호
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• pp.87-92
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• 2003

출발 물질로 TiCx(x=0.67)와 Al 분말을 사용하여 800~150$0^{\circ}C$ 온도 구간에서 상압 또는 가압 반응으로 Ti$_3$AlC$_2$를 합성하였다. 출발 물질로 TiCx(x=0.67)와 Al 분말을 사용한 반응 합성에서는 Ti-Al intermetallic compound 또는 Al-C compound와 같은 중간 형성물은 형성되지 않았으며 Ti$_3$AlC$_2$을 합성할 수 있었다. TiCx(x=0.67)와 용융 Al의 직접 반응으로 80$0^{\circ}C$에서는 Ti$_2$AlC 상이 합성되었으며, 1200~150$0^{\circ}C$ 반응온도 구간에서는 Ti$_3$AlC$_2$ 상이 우선적으로 합성되었다. 저온에서 합성된 Ti$_2$AlC 상은 고온에서 TiC와 반응으로 Ti$_3$AlC$_2$ 상으로 합성되었다. 본 연구에서는 출발 물질로 TiCx와 Al을 사용한 Ti$_3$AlC$_2$ 상의 합성기구를 제시하였다. 합성된 Ti$_3$AlC$_2$의 미세구조는 Ti$_3$AlC$_2$ 상으로 이루어진 결정립이 45~120nm크기로 적층된 구조를 갖는다.

• 한국세라믹학회지
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• 제33권2호
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• pp.223-227
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• 1996

The effect of ZrC and VC addition on the diffusion induced recrystallization (DIR) of TiC-Cr3C2 has been investigated. With in creasing the amount of added ZrC to Cr3C2 the DIR of TiC was suppressed at the begining and then occurred. On the contrary the DIR was accelerated with the addition of VC to Cr3C2 Because the lattice parameters of (Ti, Cr)C and (Ti,V)C are smaller and that of (Ti, Zr)C is larger than that of TiC the lattice parameter of (Ti,Cr,Zr)C is expected to be similar to that of TiC,. The results indicate that the strain energy due to lattice mismatch between TiC and solid-solution carbide is the driving force of the observed energy due to lattice mismatch between TiC and solid-solution carbide is the driving force of the observed DIR.

• 한국세라믹학회지
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• 제38권4호
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• pp.314-318
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• 2001

SiC-TiC composites have been fabricated by using a mechanochemical processing of a mixture of Si, Ti, and C at room temperature and subsequent hot pressing. TiC powders have been obtained by the mechanochemical processing of a mixture of Ti and C whereas SiC powders has not been obtained from a mixture of Si and C. By using the exothermic reaction between Ti and C, SiC-TiC powder could be obtained from the mixture of Si, Ti, and C using the mechanochemical processing for more than 12h. The X-ray diffraction analysis has shown that the powder subjected to the mechanochemical processing consisted of the particles having crystallite size below 10nm. Fully densified SiC-TiC composites have been obtained by hot-pressing of the powder at 1850$\^{C}$ for 3h and it has shown comparable mechanical properties to those of the SiC-TiC composites prepared from the commercially available SiC and TiC powders. Flexural strength of 560 MPa and fracture toughness of 4.8 MP$.$am$\_$1/2/ have been shown for the SiC-TiC composites with composition corresponding to 0.75:0.25:1 mole ratio of Si:Ti:C.

• 한국세라믹학회지
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• 제37권12호
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• pp.1165-1171
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• 2000

Ti-C-Ni 혼합분말을 이용하여 SHS 공정에 의해 TiC-Ni 복합체를 제조하였으며, 리칭(leaching) 공정을 통하여 Ni을 제거함으로써 TiC 분말을 얻었다. TiC 분말의 특성분석을 위하여 XRD, SEM, TEM, AES 등을 사용하였다. 리칭 공정에 의해 얻어진 TiC 분말은 구형을 유지하고 있으며, 평균 입자크기는 0.4$\mu\textrm{m}$였다. 구형 TiC 분말을 다시 Ni 분말과 혼합하여 소결한 후 특성을 분석하였다. 140$0^{\circ}C$에서 소결하였을 때 TiC 입자는 구형에서 각진 형태로 변화하였다. 기계적 특성결과 상용 TiC 분말을 사용하였을 때보다 SHS 공정에 의해 제조된 TiC 분말을 사용하여 소결하였을 경우 파괴 인성값이 약 20% 증가하였다.

• Journal of Welding and Joining
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• 제14권4호
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• pp.99-108
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• 1996

The microstructure and bond strength are examined on the SiC/SiC and SiC/mild steel joints brazed by the Ag-Ti based alloys with different Ti contents. In the SiC/SiC brazed joints, the thickness of the reaction layers at the bond interface and the Ti particles in the brazing alloy matrices increase with Ti contents. When Ti is added up to 9 at% in the brazing alloy. $Ti_3SiC_2$ phase in addition to TiC and $Ti_5Si_3$ phase is newly created at the bond interface and TiAg phase is produced from peritectic reaction in the brazing alloy matrix. In the SiC/mild steel joints brazed with different Ti contents, the microstructure at the bond interface and in the brazing alloy matrix near SiC varies similarly to the case of SiC/SiC brazed joints. But, in the brazing alloy matrix near the mild steel, Fe-Ti intermetallic compounds are produced and increased with Ti contents. The bond strengths of the SiC/SiC and SiC/mild steel brazed joints are independent on Ti contents in the brazing alloy. There are no large differences of the bond strength between SiC/SiC and SiC/mild steel brazed joints. In the SiC/mild steel brazed joints, Fe dissolved from the mild steel does not affect on the bond strength of the joints. Thermal contraction of the mild steel has nearly no effects on the bond strength due to the wide brazing gap of specimens used in the four-point bend test. The brazed joints has the average bond strength of about 200 MPa independently on Ti contents, Fe dissolution and joint type. Fracture in four-point bend test initiates at the interface between SiC and TiC reaction layer and propagates through SiC bulk. The adhesive strength between SiC and TiC reaction layer seems to mainly control the bond strength of the brazed joints.