Wear of steel plate was measured during unlubricated sliding against TiC composites. These composites consist of round TiC grains and steel matrix. TiC grain itself exhibits low surface roughness and round shape, which does not bring its counterpart into severe damage from friction. In our work a classical experimental design was applied to find out a dominant factor in counterpart wear. The analysis of the data showed that only the applied load has a significant effect on the counterpart wear. Wear rate of counterpart increased non-linearly with applied load. Amount of wear was discrepant from expectation of being in proportion to the load by analogy with friction force. Our experimental result from treating matrix variously revealed bimodal wear behavior between the composites and counterpart where a mode seems to result from the special lubricant characteristic of TiC grains, and the other is caused by metal-to-metal contact. The two wear mechanisms were discussed.

The experimental data from the central composite design runs were utilized for mathematical models far the drilling characteristics containing linear, quadratic and interactive effects of the parameters such as volume fraction of TiC in the composites, drill speed, feed rate and drill diameter. The models were developed via stepwise selection where the insignificant effects were removed using t-test. The models were subjected to optimization of maximizing drill life and satisfying the other constraints.

Mechanical properties of metal injection molded titanium and titanium alloy parts were investigated in this study. Material powders with low oxygen content and spherical shape were obtained by electrode induction-melting gas atomization which could melt and atomize titanium and titanium alloy bars with no touch on crucible or tundish. Tensile specimens were fabricated from obtained powders by metal injection molding process. Tensile strength of the specimens increases with increasing oxygen content. This result corresponds to a tendency of wrought metal.

Ultrafine titanium carbide particles were synthesized by the reaction of liquid-magnesium and vaporized TiCl+CCl(x = 1 and 2) solution. Fine titanium carbide particles with about 50 nm were successfully produced by combining Ti and C atoms released by chloride reduction of magnesium, and vacuum was then used to remove the residual phases of MgCl and excess Mg. Small amounts of impurities such as O, Fe, Mg and Cl were detected in the product, but such problem can be solved by more precise process control. The lattice parameter of the product was 0.43267 nm, near the standard value. With respect to the reaction kinetics, the activation energy for the reactions of TiCl+CCland Mg was found to 69 kJ/mole, which was about half value against the use of TiCl+CCl, and such higher reactivity of the former contributed to increase the stoichiometry until the level of TiC and decrease the free carbon content below 0.3 wt.%.

TiN barrier 막 위에 metal organic chemical vapor deposition (MOCVD)법으로 Cu막을 증착함에 있어 TiN막 표면을 먼저 세정처리하지 않고 바로 Cu막을 증착하려하면 Cu의 핵생성이 어렵고, 그 결과 연속된 Cu막이 형성되지 못한다. 본 연구에서는 SEM, AES, AFM 등의 분석방법을 사용하여 TiN 막 표면에 대한 플라즈마 전처리 세정이 Cu막의 핵생성에 미치는 효과에 관하여 조사하였다. Gu의 전처리 세정방법으로는 direct플라즈마 방식이 원거리 플라즈마 방식보다 훨씬 더 효과적이다. 또한 수소플라즈마 전처리 시 rf-power와 플라즈마 조사시간이 증가함에 따라 세정효과는 더 증대된다. 플라즈마 전처리가 Cu의 핵생성을 고양시키는 원리는 다음과 같다. 플라즈마 내의 수소이온이 TiN과 반응하여 NH3가 됨으로서 질소 성분이 제거되어 TiN이 Ti로 환원된다. Cu는 TiN기판보다는 Ti기판상에서 핵생성이 더 잘 되므로 플라즈마 전처리는 Cu의 핵생성을 돕는 효과를 가져온다.

MOCVD(Metal-Organic Chemical Vapor Dposition) TiN 박막을 다양한 온도와 압력에서 tetrakis-dimethyl-amino-titanium(TDMAT (Ti[N(CH3)2]4))의 자체 열분해와 NH3와의 반응을 사용하여 형성하였다. 비저항은 박막내의 불순물 함량에 의존하였는데 특히 XPS curve fitting 결과 주요 불순물인 탄소와 산소 같은 불순물들이 박막내에서 다양한 침입형화합물을 만들어 박막의 물리적, 전기적 특성에 영향을 준다는 것을 알았다. Metal-organic source만을 사용하여 TiN을 형성할 경우 지름이 0.5μm이고 aspect ratio가 3:1인 구멍에서 step coverage가 매우 우수하였으나 NH3를 흘림에 따라 step coverage가 감소하는 것이 SEM으로 확인되었는데 이는 각각의 활성화에너지와 관련된 것으로 보인다.