폐 MDF 폭쇄 섬유로부터의 MDF제조

이화형,서인수,조윤민,박한상,Lee Hwa-Hyoung,Seo In-Su,Cho Youn-Min,Park Han-Sang 한국가구학회 2005 한국가구학회지 Vol.16 No.1

This study was carried out to displace traditional virgin wood fiber by exploded MDF-waste fiber for the manufacture of medium density fiberboard. MDF waste was exploded in condition of $215^{\circ}C,20$ minutes. The higher the mixing ratio of exploded MDF-waste fiber, the lower the MOR and IB of MDF. There was no difference of formaldehyde emission by desiccator method between virgin wood fiber and exploded MDF-waste fiber. Adding $25^{\circ}C$ of exploded MDF-waste fiber met the KS of MDF 15 type.

고주파 평면가열에 의한 중밀도섬유판(MDF)의 핑거접합

소원택,So, Won-Tek 한국가구학회 2006 한국가구학회지 Vol.17 No.2

This experiment was carried out to investigate the high-frequency gluing characteristics of poly vinyl acetate emulsion adhesive(PVAc) on MDF edge-glued boards. The edge-glued boards were glued lengthwise with butt, scarf, or finger joint. The wastes of MDF boards were reused as board materials. The obtained results are summarized as follows; the bending strength of edge-glued MDF increased slightly with the HF heating time, but the economically desirable heating time was 6 minutes. The bending and tensile strength of edge-glued MDF were high with scarf, finger and butt joint, in order. The strength of finger jointed MDF showed 80% of scarf jointed MDF. The effects of location of finger joints on the bending strength of edge-glued MDF were larger than those of the numbers of finger joints. The bending strength of edge-glued MDF with one joint on the middle position showed 40% decrease in comparison with non-jointed MDF.

MDF를 이용한 알루미늄 평판 절개 해석

이주호(Juho Lee) 한국추진공학회 2018 한국추진공학회 학술대회논문집 Vol.2018 No.5

본 연구에서는 MDF(Mild-detonating Fuse)를 이용한 선형분리장치 개발 가능성을 확인하기 위해 기초 연구를 수행하였다. 지름이 작은 금속(납) 튜브 내부에 화약(RDX)이 충전되어 있는 MDF를 활용한 알루미늄 평판 절개 기초 시험을 수행하였다. 평판의 두께와 MDF의 단위 길이당 화약량을 조절해가며 시험을 수행하였으며, 평판 두께와 화약량에 따른 절개 여부를 확인하였다. 시험 결과를 바탕으로 AUTODYN 기반의 수치 해석 모델을 개발하였으며, 정확한 파괴 조건을 결정하였다. 시험 및 해석 결과 분석을 통해 MDF의 알루미늄 평판 절개 메커니즘과 특성을 확인하였으며, 체계 적용가능성을 확인하였다. 개발된 해석 기법을 활용하면 다양한 MDF 및 구조물에 대한 절개 가능 여부를 미리 확인하여 개발 과정에서의 시험 비용을 최소화 할 수 있다. In this paper, the possibility of the usage of MDF(Mild-detonating Fuse) for the linear separation device is studied. MDF is a small diameter metal(lead) tube filled with explosives(RDX). Aluminum plate cutting experiments with different thickness of the target plate and amount of the explosives per unit length are carried out. Based on the experimental results, the numerical analysis method including failure criteria is established. Mechanism and characteristics of the aluminum plate cutting with MDF are identified; the possibility of the current system for the linear separation device is verified. By utilizing developed numerical method, the separation reliability for diverse structures and MDF can be predicted in advance; the number of required experiments for development can be minimized.

MDF를 이용한 알루미늄 평판 절개 해석

이주호 한국추진공학회 2018 한국추진공학회지 Vol.22 No.6

본 연구에서는 MDF(Mild-detonating Fuse)를 이용한 선형분리장치 개발 가능성을 확인하기 위해 기초 연구를 수행하였다. 지름이 작은 금속(납) 튜브 내부에 화약(RDX)이 충전되어 있는 MDF를 활용한 알루미늄 평판 절개 기초 시험을 수행하였다. 평판의 두께와 MDF의 단위 길이당 화약량을 조절해가며 시험을 수행하였으며, 평판 두께와 화약량에 따른 절개 여부를 확인하였다. 시험 결과를 바탕으로 AUTODYN 기반의 수치 해석 모델을 개발하였으며, 정확한 파괴 조건을 결정하였다. 시험 및 해석 결과 분석을 통해 MDF의 알루미늄 평판 절개 메커니즘과 특성을 확인하였으며, 체계 적용가능성을 확인하였다. 개발된 해석 기법을 활용하면 다양한 MDF 및 구조물에 대한 절개 가능 여부를 미리 확인하여 개발 과정에서의 시험 비용을 최소화 할 수 있다. In this paper, the possibility of using an MDF (Mild-detonating Fuse) as a linear separation device is studied. An MDF is a small diameter metal (lead) tube filled with explosives (RDX). Aluminum plate cutting experiments are carried out with different values of target plate thickness and explosives per unit length. Based on the experimental results, a numerical analysis method including the failure criteria is established. The mechanism and characteristics of using MDFs for aluminum plate cutting are identified; the possibility of using the current system as a linear separation device is verified. By utilizing a developed numerical method, the separation reliability for diverse structures and MDFs can be predicted in advance and the number of experiments required for development can be minimized.

폐MDF의 해리와 고해처리를 통한 고밀도 Fiber Board제조

이화형,서인수,조윤민,박한상,Lee, Hwa-Hyoung,Seo, In-Su,Cho, Youn-Min,Park, Han-Sang 한국가구학회 2006 한국가구학회지 Vol.17 No.1

This study was carried out to resplace traditional virgin wood fiber by recycled MDF-waste fiber for the manufacture of high density fiberboard. For the recycling, MDF waste was disintegrated for 10 minutes and beaten for 15 minutes. There was no difference in formaldehyde emission by desiccator method between virgin wood fiber and disintergrated and beaten MDF-waste fiber. Fiberboard which was maded from 100% of disintergrated and beaten MDF-waste fiber showed similar physical and mechanical properties to those of virgin fiber. The yield of recycled fiber from MDF waste was 85%.

내부천공이 중밀도 섬유판(MDF)의 종압축강도에 미치는 영향

蘇元澤 전남대학교 농업과학기술연구소 2000 農業科學技術硏究 Vol.35 No.-

This experiment was carried out to investigate the effect of internal holes on the compressive strength parallel to the grain of MDF. The diameters of holes are 5mm to 21mm, the locations of holes are 1/2 to 1/5 point from sample ends, and the numbers of holes are 1 to 4 pcs. In the size of internal holes, the compressive strengths of MDF were decreased significantly with the increase of diameter of holes, and the relationship between diameters(D) of holes and compressive strength(σc) of MDF is σc=-5.26D+144.39, (r=-0.99**). The effects of hole-locations on the compressive strengths of MDF were very small. The compressive strengths of MDF were decreased with the increase of number of holes, but the decreasing rate were very small.

In vitro evaluation of a removable partial denture framework using multi-directionally forged titanium

Suzuki, Ginga,Shimizu, Satoshi,Torii, Mana,Tokue, Ai,Ying, Guo,Yoshinari, Masao,Hoshi, Noriyuki,Kimoto, Katsuhiko,Miura, Hiromi,Hayakawa, Tohru,Ohkubo, Chikahiro The Korean Academy of Prosthodonitics 2020 The Journal of Advanced Prosthodontics Vol.12 No.6

PURPOSE. This study evaluated the availability of multi-directionally forged (MDF) titanium (Ti) as a component of removable partial dentures (RPDs). MDF-Ti remarkably improved the mechanical properties of RPDs due to its ultrafine-grained structure. MATERIALS AND METHODS. The wear resistance, plaque adhesion, and machinability of MDF-Ti were tested. As controls, commercially pure (CP) titanium was used for wear, plaque adhesion, and machinability tests. For wear resistance, the volume losses of the titanium teeth before and after wear tests were evaluated. Plaque adhesion was evaluated by the assay of Streptococcus mutans. In the machinability test, samples were cut and ground by a steel fissure bur and carborundum (SiC) point. An unpaired t-test was employed for the analysis of the significant differences between MDF-Ti and the control in the results for each test. RESULTS. Wear resistance and plaque adherence of MDF-Ti similar to those of CP-Ti (P>.05) were indicated. MDF-Ti exhibited significantly larger volume loss than CP-Ti in all conditions except 100/30,000 g/rpm in machinability tests (P<.05). CONCLUSION. Although the wear resistance and plaque adherence of MDF-Ti were comparable to those of controls, MDF-Ti showed better machinability than did CP-Ti. MDF-Ti could be used as a framework material for RPDs.

폐MDF를 이용한 염색재생섬유 제조

주선경 ( Seong-gyeong Ju ),노정관 ( Jeongkwan Roh ) 한국목재공학회 2017 목재공학 Vol.45 No.3

폐MDF 재생섬유를 인테리어 소품 제조용 원료로 이용하기 위해 MDF 제조용 리기다소나무 버진섬유와 MDF를 제조한 후 재해섬한 재생섬유에 대해 빨강, 노랑 및 파랑색 계열의 Bis-monochlorotriazine (MCT)계와 Vinyl sulfone(VS)계의 반응성염료, Anthraquinone계의 배트염료, Diazo계열의 직접염료 및 치자와 소목의 천연염료에 의한 염색 특성 및 일광견뢰도를 검토하였다. 염색 전의 버진섬유와 재생섬유의 색상은 각각 4.2YR과 4.4YR로 약간의 적색기가 있는 황색을 나타내고 있었으며, 재생섬유가 버진섬유에 비해 L^*의 값이 작아 약간 더 어두웠다. 적, 청, 황색계의 MCT계와 VS계의 반응성염료, 배트염료, 직접염료 모두 버진섬유와 재생섬유에 관계없이 염색은 매우 양호하게 잘 이루어졌다. 재생섬유가 버진섬유보다 염착량은 약간 높았고, L^*와 V의 값은 약간 감소하였으나, 큰 차이는 없었다. 일광견뢰도는 염료에 따라 약간의 차이는 있으나 버진염색섬유가 재생염색섬유보다 더 큰 색차를 보이고 있어 불량하였다. 소목으로 염색한 재생섬유와 버진섬유의 색상은 각각 4.4YR과 4.0YR로 염색 전의 미염색 섬유와 거의 차이가 없었으나, 치자로 염색한 섬유의 색상은 각각 7.4YR과 6.9YR로 황색계의 반응성염료, 배트염료 및 직접염료보다 큰 색차를 보여 염색성은 우수하였으나 일광견뢰도는 불량하였다. This research was performed to use recycling wood fiber from waste MDF as raw materials for manufacturing of interior decorative accessories. Virgin fiber of Pinus rigida for manufacturing MDF and recycling fiber from manufactured MDF with virgin fiber were dyed by using reactive dyes (Bis-monochlorotriazine and Vinyl sulfone type), vat dyes (Anthraquinone type), direct dyes (Diazo type) such as red, yellow and blue, and natural dyes using gardenia or sappan wood, and they were examined to evaluate their dyeing properties and sunlight fastness. The hue of virgin fiber and recycling fiber were 4.2YR, and 4.4YR, respectively, which showed red-yellowish color. The recycling fiber looked a little darker than the virgin fiber, where L^* values of the recycling fiber showed a little lower. Reactive, vat and direct dyes dyed well both the virgin and recycling fibers. The recycling fiber showed a little higher values of colour yield and a little lower in L^*, but it seemed that there was no significant difference. The Hue values of the recycling fiber and the virgin fiber dyed with sappan wood were 4.4YR and 4.0YR, showing no difference between/after dyeing. However the Hue values of the recycling fiber and the virgin fiber dyed with gardenia were 7.4YR and 6.9YR, respectively. Those values were much higher than the values of the fibers dyed with other chemical dyes. But the fibers dyed with gardenia showed poor sunlight fastness.

탄화보드를 이용한 서각작품 제작

박상범 ( Sang Bum Park ),정성호 ( Song Ho Chong ),변희섭 ( Hee Seop Byeon ),류현수 ( Hyun Soo Ryu ) 한국목재공학회 2010 목재공학 Vol.38 No.3

중밀도섬유판(MDF)에 글씨나 그림을 새김질한 목판을 제조하고, 이를 탄화하여 서각작품을 제작하는 방법을 개발하였다. 섬유판의 탄화에 따른 외형적 및 조직학적 변화를 검토하고 제작된 탄화보드 서각작품에 대한 미학적 특징을 고찰하였다. 서각한 MDF를 850°C에서 탄화한 결과, 할열이나 뒤틀림은 관찰되지 않았으며, 치수는 가로 21.8%, 세로 18.8%, 두께 43.5% 줄어들었고, 중량은 69.2%, 밀도는 14.8% 감소하였다. 탄화보드의 전자 현미경에 의한 관찰 결과, 당초 섬유의 표면과 벽공을 둘러싸고 있던 접착제가 탄화되면서 목질섬유의 표면이 매끄럽게 변하고 벽공이 개열되며 섬유의 크기가 균일화되고 조직이 치밀화되는 현상을 나타내었다. 수작업에 의한 서각기법과 무할열 탄화기법의 융합에 의해 새로운 탄화보드 서각작품의 제작이 가능하였다. 탄화보드 서각작품은 목탄의 기능성과 서각의 아름다움을 부여하는 새로운 친환경 예술영역의 한 분야로서 이용될 수 있을 것이다. This study was focused to make a wooden plate that is engraved with writings or pictures on the medium density fiberboard (MDF), and then to produce a calligraphy-carving artwork by carbonization of the carved MDF. The external appearances and anatomical changes were investigated on the carbonized MDF and aesthetic characteristics was also discussed. No split and no twist were found after the carbonization (at 850°C) of the calligraphy-encarved MDF, shrinkages of the MDF were observed with portions of 21.8% in length, 18.8% in width and 43.5% in thickness, and 69.2% of weight loss with density decrease of 14.8% were observed as well. From the observation of the carbonized board by a scanning electron microscope, specific phenomena were found: the adhesives, surrounding the fiber`s surface and pits, were carbonized, the woody fibers were changed smoothly, the pits were opened, the fiber`s size was uniformized, and the organization was compacted. By the combination of handmade calligraphy-woodcarving and crack-free carbonizing methods, it was able to find a new method for manufacture carbonized calligraphy-woodcarving artwork. It is concluded that the calligraphy-woodcarving artwork using carbonized board can be a new access for the eco-friendly art that has the advantage of the functionality of charcoal and the aesthetic of calligraphy-woodcarving simultaneously.

MDF철가 내진설계를 통한 보강방안 강구

홍진표 ( Hong Jin-pyo ),김진귀 ( Kim Jin-gwi ),박용면 ( Park Yong-myun ),장원복 ( Chang Won-bok ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.1

국내최대 통신사업자인 KT는 초고속 인터넷, IP-VDSL 시설 시공 등으로 인해 전화국내 케이블 적재량 증가 및 광케이블 포설 등으로 인하여 MDF철가 상단에 사용중인 케이블과 유휴 케이블이 서로 얽혀 포설되어 있어 선별철거가 어렵고 전화국내유휴케이블의 과적재와 철가 노후로 인하여 MDF철가 구조물의 변형이 발생되고, 진행됨에 따라 MDF 기울어짐 및 붕괴 등의 대형통신사고 발생우려가 있어 안전성 검토를 통한 보완책이 필요하게 되었고, 현재 KT전화국 건물은 통신건물의 특수성을 감안하여 건축구조물에 대한 내진설계를 하여 안전성이 확보되어 있으나, 통신선로가 최종적으로 집적되어 관리되고 있는 MDF(고객회선관리실) 철가에 대하여는 내진에 대한 검토가 이루어지지 않아 매년 증가되는 지진에 대한 안전성 확보를 위해 내진 검토를 통하여 안전성을 확보토록 하였다.