MDF로 제조된 우드세라믹의 성질

오승원,변희섭 한국목재공학회 2002 목재공학 Vol.30 No.2

MDF를 페놀수지에 함침한 후 500, 650, 800, 1,000℃에서 소성하여 우드세라믹을 제조한 후 함침재 및 우드세라믹의 치수 변화와 휨강도를 측정하였다. 수지 함침율이 증가할수록 함침재의 치수 증가율 및 휨강도는 증가하였다. 소성온도에 따른 중량, 길이 및 두께감소율은 각각 소성온도 500℃ 일 때 59.9%, 19.4%, 26.3%이었으며, 소성온도 1,000℃ 일 때 65.3%, 22.5%, 31.0%로 소성온도가 증가함에 따라 증가하였으며, 휨강도 또한 함침율 40%일 때 소성온도 500℃ 에서 50.3 kgf/㎠, 1,000℃ 에서 142.0 kgf/㎠로 증가하였다. 소성 후의 밀도는 함침율 40%일 때 소성온도 500℃ 에서 0.70 g/㎤, 800℃ 에서 0.79 g/㎤로 증가하였으나, 1,000℃ 에서는 0.75 g/㎤로 약간 감소하였다. 이상의 결과로 함침재 및 우드세라믹의 성질은 수지 함침율 및 소성온도의 영향을 받음을 알 수 있었다. Woodceramics are new porous carbon materials obtained by burning wood or woody materials impregnated with thermosetting resin in a vacuum furnace. In this paper, the change of dimensions and bending strength of woodceramics which were made from medium density fiberboard have been investigated to examination the possibility of utilization as a woodceramics materials. 1) An increasing rate of dimension in impregnated board increased with increasing resin impregnation rate. And increasing rate of thickness was higher than that of length. 2) When the resin impregnation rate increased, the bending strength of impregnated board had a tendency to increase. 3) The rates of weight loss, length and thickness reduction of woodceramics showed a slight increase with increased burning temperature. 4) The density of woodceramics showed a increase from at 500℃ till at 800℃ with increasing burning temperature but decrease at 1,000℃. 5) When the burning temperature increased, the bending strength of woodceramics had a tendency to increase.

열수 및 마이크로웨이브처리 맹종죽재의 물리적·기계적 특성

신훈재,안상열,변희섭,박상범,공영토 한국목재공학회 2004 목재공학 Vol.32 No.2

열수 및 마이크로웨이브조사 처리가 별채시기 및 부위별에 따른 맹종죽재의 물리적 기계적 특성을 평가하고, 효율적인 연화조건을 탐색하기 위하여 경남 진주시 가좌동에 위치한 남부임업시험장내에서 생육이 양호한 1, 2, 3년생의 죽재를 8월과 1월에 벌채하여 실험한 결과는 다음과 같았다. 1. 윗부위, 중간부위, 아랫부위의 부위별에 따른 휨탄성계수의 차이는 윗부위가 가장 높은 값을 나타내었고 중간부위, 아랫부위 순으로 낮은 값을 나타내었으며 대부분이 70,000~110,000 kgf/㎠의 범위에 있었다. 2. 동적 탄성계수의 범위는 80,000~130,000 kgf/㎠의 범위로 정적 탄성계수보다 10~25% 정도 높게 나타났으며, 8월과 1월의 상관관계 R값이 각각 0.87과 0.68로 나타나 일반적인 목재와 같이 맹종죽재의 탄성계수 측정에도 비파괴 방법인 양단자유진동에 의해서도 예측 가능하였다. 3. 95℃의 열수로 처리했을 때 연화율은 10~30%를 나타내었다. 4. 생재 및 포수 두 조건 모두 마이크로웨이브조사 처리 시간이 길어질수록 탄성계수가 낮아졌으며, 20초 및 30초간 처리했을 때 생재 휨탄성계수의 약 50% 이하로 떨어져 생재를 20초간 마이크로웨이브조사 처리했을 때가 본 연구에서 죽재를 연화시키는데 가장 효과적인 방법이었다.

직물유리섬유 강화집성재의 물리적 특성 (제1보) : 기계적 특성 Mechanical Properties

정인석,이원희,변희섭 한국목재공학회 2003 목재공학 Vol.31 No.5

본 연구는 국산소경재인 소나무(Pinus densiflora)재와 낙엽송(Larix kaemferi)재로 제조된 유리섬유강화집성재의 강도적 성질을 조사해 보기 위하여 실시되었다. 먼저, 직물 유리섬유를 수성고분자-이소시아네이트계(MPU-500) 접착제를 사용하여 control재와 유리섬유를 각각 1층과 2층 함입하였다. 본 연구의 결과는 다음과 같다 1. 수성고분자-이소시아네이트 수지는 집성재 제조용으로 적합하였으며. 특히 유리섬유를 2층 함입한 소재를 제외하고는 구조용 집성재의 품질기준(KS F 3021)을 만족시켰다. 2. 직물유리섬유를 함입할 경우 휨강도, 전단강도에서 control재보다 크게 뛰어나지는 않았지만, 비례한도 휨응력은 유리섬유의 함입 층수에 비례하여 증가하였다. 그러므로, 직물 유리섬유의 mesh수와 두께를 집성재 소재의 형태에 따라 적절히 조정한다면, 휨강도와 전단강도를 좀더 향상시킬 수 있을 것으로 판단되었다. This study was carried out to investigate the mechanical properties of fabric E-glass fiber reinforced laminated timber. Specimens used to Korean red pine(pinus densiflora) and Japanese larch(Larix Raemfert). Fabric E-glass fiber was inserted in the solid wood with aqueous polymer-isocyanate resin(MPU-500). The results were as follows: 1. Aqueous polymer-isocyanate resin(MPU-500) was good resin to manufacture laminated timber. specially, it was satisfied to property standard of construction laminated timher(KS F 3021) except for two ply glass fiber. 2. Bending and shear strengths of solid wood inserted with fabric glass fibers were not different from control solid wood. But, proportional limit bending stress was increased following the number of fabric glass fibers. Therefore, it was considered that to improve the bending and shear strength of fabric glass fiber reinforced laminated timber, the glass fiber thickness and its mesh should be modified to fitness following working conditions.

E-Mobile System을 이용한 국립공원 관리시스템 설계

오세진,안상렬,변희섭,마호섭 경상대학교 농과대학 부속연습림 2001 演習林硏究報告 Vol.- No.11

In this paper, we developed a design model for integral administration of national parks using E-Mobile system, which combined Geographical Information System(GIS) and Geographical Positioning System()GPS . This E-Mobile system will contribute to the systematic administration in the national parks by recording geographical information of the national parks by GIS, as well as an individual route guide within the parks by GPS with satellites. Finally, this paper will considerably contribute to the systematic and integral organization of the national parks organization by the newly developed E-Mobile system.

염색 단판을 이용한 集成 染色 무늬목 開發

안삼근,강형철,안상열,이균필,변희섭 경상대학교 농업생명과학연구원 2002 농업생명과학연구 Vol.36 No.4

본 연구는 집성 염색 무니목 개발을 위하여 사용 가능한 수종과 3종류의 염료를 사용하여 염색시간, 염색온도, 함수율 및 Flitch 제작에 대하여 연구한 결과는 다음과 같다. 실험에 사용한 4수종 중에서 선삭성이 불량한 은수원 사시나무를 제외한 3수종인 소나무와 이태리 포플러, 마티카가 사용 가능한 수종으로 밝혀졌다. Stain은 번지거나 얼룩이 지는 현상, Dylon은 침투 불균일로 부적당하였으나 Fine은 염색상태가 양호하였다. 염색시간은 5시간 이상 되어야 염색정도가 양호하였고, 염색온도는 90℃에서 가장 적당하였으며 생재와 기건재 및 포수재에 대한 영향은 큰 차이가 없었다. Flitch제작에 적당한 함수율은 9%이었다. This study was carried out to develop laminated dyeing wood, for which usable three sixties of trees and 3 kinds of dye stuffs were used to investigate dyeing time, dyeing temperature, moisture content and manufacture of flitch, the results were as follows: Out of four species of trees used in the experiment, it was found that three species, Pinus densiflora, Populus euramercana and Dyrea costulata were usable excluding Populus tomentiglandulosa whose cutting ability was bad. As to influence according to the kind of dye stuff, the Stain of low price could be used as a coloring agent but it was not proper as a dyeing agent due to spreading or staining phenomenon. As Dylon which was generally used to dye textile penetrated them uneven, dyeing only their surface, it was also found improper to be used. On the other hand, the dyed condition was good with Fine. The dyed condition was good when dyeing time was more than 5 hours and it was the most adequate when the temperature was at 90℃. There was no significant difference between their influence on green, dried and saturated wood.-In the manufacture of Flitch, the most appropriate moisture content was 9%.

Sound Absorption Property of Heat-Treated Wood at A Low Temperature and Vacuum Conditions

Hee Seop Byeon,Jung Hwan Park,Kyo Kil Hwang,Han Min Park,Beyung Soo Park,Song Ho Chong 한국목재공학회 2010 목재공학 Vol.38 No.2

Nondestructive Evaluation of Bending Strength Performances for Red Pine Containing Knots Using Flexural Vibration Techniques

Hee Seop Byeon,Sang Yeol Ahn,Han Min Park 한국목재공학회 2005 목재공학 Vol.33 No.5

Nondestructive Bending Strength Evaluation of Ceramics Made from Miscanthus sinensis var. purpurascens Particle Boards - Effect of Resin Impregnation Ratio -

Hee Seop Byeon,Kyung Rok Won,Seung Won Oh 한국목재공학회 2014 목재공학 Vol.42 No.2

Nondestructive evaluation (NDE) method by using a resonance frequency mode was carried out for ceramics made from particle boards with different phenol resin impregnation ratios (30, 40, 50, 60%) at carbonizing temperature of 800℃. The material for ceramics was Miscanthus sinensis var. purpurascens board. Dynamic modulus of elasticity in-creased with increasing impregnation ratio. There was a close relationship of dynamic modulus of elasticity and static bending modulus of elasticity to modulus of rupture (MOR). However, the result indicated that correlation coefficient is higher in dynamic modulus of elasticity to MOR than that in static modulus of elasticity to MOR. Therefore, the dynamic modulus of elasticity using resonance frequency by free vibration mode is more useful as a nondestructive evaluation method for predicting the MOR of ceramics made from Miscanthus sinensis var. purpurascens particle boards by different phenol resin impregnation ratios.

Mechanical Properties of Woodceramics According to Carbonizing Temperature : Bending, Compression and Hardness

Byeon, Hee-Seop,Ahn, Sang-Yeol,Oh, Seung-Won,Piao, Jin-Ji 한국목재공학회 2004 목재공학 Vol.32 No.3

This paper reports the mechanical properties of bending, compression and hardness of woodceramics manufactured at different carbonizing temperatures (600℃, 800℃, 1000℃, 1200℃ and 1500℃) in a vacuum sintering furnace using sawdust boards of Pinus densiflora, Pinus koraiensis and Larix kaemferi. The highest values of bending MOR(MOR_(b)) were 104 kgf/㎠ (1200℃), 91 kgf/㎠ and 86 kgf/㎠ (1500℃), the highest values of compression strength were 152 kgf/㎠ (1200℃), 160 kgf/㎠ (1000℃), and 189 kgf/㎠ (1000℃), the highest values of hardness were 2.00 kgf/㎠ (800℃), 2.01 kgf/㎠ (1200℃) and 2.28 kgf/㎠ (1000℃) in P. densifora, L. kaemferi and P. koraiensis, respectively. The carbonizing temperature of 600℃ was not proper to the mechanical properties for three kinds of sawdust boards and the highest values of mechanical properties were different from the kinds of mechanical properties and species of sawdust boards. Therefore, it is necessary to manufacture woodceramics at a proper temperature for particular species of sawdust boards to obtain good mechanical properties.

Nondestructive Bending Strength Evaluation of Woodceramics Using Resonance Frequency Mode (Ⅰ) : Carbonizing Temperature

Byeon, Hee-Seop,Ahn, Sang-Yeol,Oh, Seung-Won,Piao, Jin-Ji 한국목재공학회 2004 목재공학 Vol.32 No.3

Nondestructive evalution (NDE) technique method using a resonance frequency mode was carried out for woodceramics produced at different carboniing temperatures (600℃, 800℃, 1000℃, 1200℃, 1500℃) at the phenol resin impregnation rate of 70%, for three kinds of species (Pinus desifora, inus koraiensis, Larix leptolepis), respectively. There was a poor relationship between density and static bending MOR. However, close correlations were found between dynamic MOE_(d) and static bending MOR, and between static MOE_(S). Therefore, the MOE_(d) using the resonance frequency mode is useful as a NDE method for predicting the MOR of Woodceramics produced at different carbonizing temperatues.