Titanium has many special characteristics such as specific high strength, low elastic modulus, excellent corrosion and oxidation resistance, etc. Beta titanium alloys, because of their good formability and strength, are used for jet engines, and as turbine blades in the automobile and aerospace industries. Low cost beta titanium alloys were developed to take economic advantage of the use of low-cost beta stabilizers such as Mo, Fe, and Cr. Generally, adding a trace of boron leads to grain refinement in casted titanium alloys due to the pinning effect of the TiB phases. This study analyzed and evaluated the microstructural and mechanical properties after plastic deformation and heat treatment in boron-modified Ti-2Al-9.2Mo-2Fe alloy. The results indicate that a trace of boron addition made grains finer; this refinement effect was found to be maintained after subsequent processes such as hot forging and solution treatment. This can effectively reduce the number of required manufacturing process steps and lead to savings in the overall cost as well as low-cost beta elements.

Metastable phase characteristics of beta Ti alloys were investigated to consider the relationship of the microstructureand diffraction pattern in TEM. TEM analysis showed that the microstructure was mottled as a modulated structure, and thediffraction pattern was composed of spot streaks between the main spots of a stable beta phase with a specific latticerelationship. The modulated structure may be induced by short distance slip or atom movement during a very short intervalof solution treated and quenched (STQ) materials. The athermal ω phase, which could be precipitated at low temperature aging,is also analysed by the metastable phase. The metastable phases including athermal ω phase had a common characteristic ofhardened and brittle behavior because the dislocation slip was restricted by a super lattice effect due to short distance atommovement at the metastable state.

경상분지 중앙부에 분포하는 백악기 하부 하양층군의 사암과 이암에서 산출되는 속성광물은 탄산염 광물(방해석, 백운석), 점토 광물(I/S, C/S, 일라이트, 녹니석 및 캐올리나이트), 알바이트, 석영 및 적철석이 대부분을 이루고 있다. 각 층별 특징적인 속성 광물상으로는, 칠곡층에서는 알바이트-녹니석(C/S포함)-적철석이, 신라역암은 알바이트-일라이트-방해석이, 함안층에서는 일라이트-녹니석-적철석이, 반야월층에서는 알바이트-녹니석-백운석이 산출된다. 속성 작용 과정의 물리, 화학적 환경 변화를 지시하는 점토 광물로는 일라이트가 전층군을 통하여 보편적으로 산출되나, 녹니석(C/S포함)은 회색 또는 녹색암이나 화산기원 물질의 함량이 높은 칠곡층 사암과 이암에서 주로 나타난다. 이러한 속성 광물상에 근거할 때, 속성 광물의 생성은 일차적으로 기원암과 밀접히 연관된 것으로 판단된다. 또한, 일라이트 결정도를 기준으로 이 지역의 사암과 이암은 후기 속성 작용 단계 내지 저변성 단계에 해당되며, 속성 작용은 매몰 심도 보다 백악기 화강암체의 관입, 유기물의 함량과 입자의 크기 및 퇴적환경의 영향을 크게 받은 것으로 보인다.

Yin and Yang are a general idea to understand phenomenon and human body. Specially in medicine, the principle of Yin and Yang is clinical and positive. As the principle of Yin and Yang, the human body can be seperated two parts; male-female, upward-downward, front-rear, left-right, interior-exterior, inside-outside and heat-cold, input-output, contraction-relaxation, hard-soft, active-pasive, weekness-strong and old-young, white-black, fat-lean, high-low, long-short, spirit-body. But, Yin and Yang are facing and interchanging each other. Summaries of a study on the means of yin and yang in Naekyoung and Waekyung chapter of DongEuiBoKahm are as follows. 1. Yin and Yang represent Objects . They represent natural phenomena; for example the situation of weather and time is expressed by them. . They represent urinary organ, anus, genital organ. . They represent the five viscera and the six entrails and their functions. . They represent male and female. . They represent fat and lean. 2. Activity and Inactivity are represented by Yin and Yang. ；They mean increasing of temperature by activity and decreasing of temperature by inactivity. . They mean the movement and activity of Ki 3. Yin expresses formation and Yang expresses functions. . Ki and it's functions are expressed by Yin and Yang. . Body fluid, blood and fundamental nutrition are expressed by Yin and Yang ；Organic system of human body and functions of organs are expressed by Yin and Yang. 4. The directions in human body and direction of Ki are expressed by Yin and Yang ；Inside and Outside of human body are expressed by Yin and Yang. . Emission and contraction is expressed by Yin and Yang. ․Upper and lower side of human body are separated by Yin and Yang. ․Upward and downward flow of Qi is expressed by Yin and Yang. . They represent KyungNak, YoungKi, WeKyung.a

반응생성에 의한 Ti/TiB 복합재료를 제조하기 위한 반응분말(TiB2, B4C), 소결온도, 소결시간을 결정하기 위하여 제조조건에 따른 반응생성상, 미세조직, 상대밀도 등을 조사하였다. 제조된 복합재료의 기계적 성질은 상온 압축항복강도로 평가하였다. 복합재료를 제조하기 위하여 혼합하는 TiB2반응분말의 경우 1300˚C, B4C 반응분말의 경우 1400˚C의 소결온도가 최적조건임을 확인하였다. 본 공정에 의해서 제조된 복합재료의 압축항복강도는 비교재인 Ti-6Al-4V 보다 모두 우수하였다. 또한 TiB2반응분말에 의해서 제조된 복합재료가 B4C 반응분말에 의해서 제조된 복합재료보다 우수한 압축항복강도를 나타내었다. 이는, 압축시험한 복합재료에서의 균열전파양상을 조사한 결과, 강화상과 기지간의 접합특성을 B4C 반응분말에 의한 복합재료의 접합특성보다 우수하였기 때문이었다.