Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Internal Void Structure of Strandboard using X-ray Computed Tomography

X-ray 단층촬영기법을 이용한 스트랜드보드의 내부공극구조에 관한 연구

  • Received : 2008.05.14
  • Accepted : 2008.07.01
  • Published : 2008.11.25
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Abstract

Internal voids affecting the mechanical properties of wood composite were classified into two catagories and characteristics of voids were examined according to density variation of strandboard. The void distribution and content of strandboard according to board density were measured by X-ray computed tomography system and analized using image processing software. Prior to investigation, the densities of strandboard were measured by densitometer and the results were showed high correlation with conventional oven drying method. Based on the image analysis conducted on captured images by X-ray tomography, low resolution can be used to capture the macro-voids (between strand) but not the micro-voids (within strands). Intermediate resolution can be used to capture both the macro and the micro-voids and high resolution can be successfully used to capture the majority of the micro-voids. The content of macro-void was measured and content of micro-void was computed by corresponding related equation. The macro-void distribution can be successfully understood and void content can be correctly estimated through the results.

보드의 기계적 성질에 영향을 미치는 공극에 대하여 공극을 두가지로 분류하고 밀도에 따른 오에스비의 내부 공극구조의 특성에 대하여 살펴보고자 하였다. 스트랜드보드의 내부공극을 X-ray 단층촬영기로 측정하고 이미지분석 소프트웨어를 사용하여 밀도에 따른 공극의 분포와 공극의 함유량을 조사하였다. 측정 전에 보드의 밀도를 밀도측정기와 전건법으로 측정하였으며 이 두 방법에 의해 측정된 결과는 아주 높은 상관관계를 보여주었다. X-ray를 서로 다른 배율로 조사하여 획득한 이미지를 바탕으로 분석한 결과, 저해상도에서는 스트랜드간의 공극(macro-void)의 측정이 가능하나 스트랜드내의 미세공극(micro-void)은 이미지획득이 불가능하였다. 중해상도에서는 두가지 형태 모두의 이미지 획득이 가능하였고, 고해상도에서는 대부분의 미세공극 이미지의 획득이 가능하였다. 저배율을 채택하여 스트랜드간의 공극을 측정하고 스트랜드내의 미세공극은 관련식을 이용하여 추정하였다. 이를 통해 보드내부에 존재하는 스트랜드간의 공극분포를 파악할 수 있었으며 그 공극의 함유비율을 정확하게 산정할 수 있었다.

Keywords

Acknowledgement

Supported by : 대구대학교

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