• Electrical & Electronic Materials
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• v.6 no.3
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• pp.214-219
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• 1993

고온에서 실리콘에 인을 확산시키기 위한 새로운 고체 판상 원료를 개발하였다. Source Wafer는 거품 형태의 골결을 지닌 불활성 재료에 Yttrium metaphosphate가 들어있는 구조로 되어있다. 새로운 고체 판상 원료를 사용하여 고온에서 인을 확산시켜서 재현 가능한 Sheet resistance와 깊은 Junction을 얻었다. 일련의 한 시간 도핑 결과들로부터 새로운 고체 판상 원료의 수명은 40시간 이상인 것으로 판명되었다. 1150.deg.C에서 인의 실리콘에로의 확산에 대한 유효 확산계수와 대응되는 활성화 에너지의 값을 구하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.95-95
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.45-45
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• 1994

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.05a
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• pp.16-16
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• 1993

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.75.2-75.2
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• 2007

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.48-48
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• 2003

가스터빈 핵심부품은 모두 고온고압의 열악한 환경에서 사용되므로 정기적으로 열화상태를 파악하여 신품으로의 교체 또는 재생 정비해야 한다. 그러나 국내의 재생 정비기술의 낙후로 인해 재생 가능한 고가의 부품까지 폐기, 교체함으로써 발전원가 상승의 주 요인이 되고 있다. 본 연구에서는 발전용 GT 블레이드 재료인 IN738LC 및 GTD111 판상시편에 대하여 다양한 용접 방법과 변수로 PTA 육성용접하였으며, 각 변수에 따른 미세조직 변화를 관찰하고 모의결함 시편에 대해 기계적 물성을 평가하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.6
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• pp.292-298
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• 2002

Densified cordierite matrixes added alumina platelets were studied as a ceramic substrate material having a low thermal expansion coefficient, low dielectric constant and proper strength. Amorphous-type cordierite powders were filled with four kinds of alumina platelet powders in various compositions. All samples were sintered at $1300^{\circ}C$ for 2 h in an air atmosphere. Improved flexural strength of about 80 MPa, low dielectric constant of 5.0 at 1 MHz and low thermal expansion coefficient of $3.5 \times 10^{-6}/^{\circ}C$ were obtained by the control of the microstructure. Isolated micropores were formed in the matrix and the porosity was dependent on the platelet content and size. In the 10 vol% of alumina platelet content, the isolated micropores were 3~8 $\mu \textrm{m}$ in size, and an increase in dielectric constant by adding alumina platelet filler was inhibited by the micropores.

• Korean Institute of Interior Design Journal
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• v.16 no.5
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• pp.98-106
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• 2007

With the recent increase in the amount of interior materials, the medium-density fiberboard(MDF) has continued to be produced at an increasing rate. Accordingly, to prevent the deformation of MDF after its construction, secure the precision of its finishing and improve the performance of its design, this study attempted to investigate the effect of environment humidity conditions on flatness according to the field used in MDF and its relationship to other physical properties. An attempt was made to conduct this study by changing the conditions of surface treatment by moisture and by thickness. For this purpose, it is judged that it is desirable to prevent scheme to maintain the flatness by defining the coefficient of water absorption-induced length change as in the regulation on low-density soft fiberboard and adjusting the standard for wet bending strength upward. It is thought that is further studies will be conducted about the effect of material, adhesive and thermal pressure condition, production system and processing method used in MDF on its scheme to maintain the flatness and changes in length and thickness expansion.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.157-160
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• 2000

흡음원리의 측면에서 저음의 흡음은 재료 자체에서의 효과보다는 그 재료의 배열에서 발생하는 공명등의 역할이 크다. 따라서 단일흡음재료 보다는 공명체나 판상재와 다공질 흡음재, 그리고 그 배후의 공기층에 의해 구성되는 복합적 흡음구조가 더욱 효과적인 저음흡음재가 될 수 있다. 본 연구에서는 여러 가지 목재나 철제의 슬릿, 그리고 철제나 MDF 재질의 유공판을 표면재료로 하는 저음흡음구조를 설계하기 위한 준비단계로서 저음흡음구조에서 표면재료의 번화가 가져올 수 있는 흡음특성의 차이를 알아보고자 한다.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.396-400
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• 1989

The oxygen index test was carried out to obtain the relative flammability of wood-based materials (plywood, MDF, particleboard) and their oxygen indices. The oxygen index is the minimum concentration of oxygen, expressed as volume percent, in a mixture of oxygen and nitrogen that will just support flaming combustion of a material under the specified laboratory conditions. In this study the oxygen indices were calculated by using the Dixon and Massey's Up and Down method("N" Large method). The obtained results were as follows : 1. The oxygen indices calculated with Up and Down method were 27.9% for plywood, 26.9% for MDF, and 26.2% for particleboard, indicative of plywood being more difficult to burn than MDF and particleboard Lender the same surrounding conditions. 2. The oxygen indices were not affected by the total gas flow rate.