杉木定向粒片板之定向率超音波傳播速度之關係

The Relationship between the Degree of Flake Alignment and Sound Velocity of China Fir OSB

陳柏璋(Bor-Jang Chen) ； 王松永(Song-Yung Wang)

《林產工業》 18卷3期 (1999/09) Pp. 269-278

摘要

定向拉片板定向率累計至15°時，已佔全部長薄片型拉片之2/3，具優良定向效果。全板面板木理方向與機械方向成平行之音速（V//）為４586-4632 m／sec；而面板木理方向與機械方向成垂直之音速（V┴）為1430~1565 m/sec。V//／V┴之比值，約2.93~3.24之間。音速值會隨θ°之增加而遞減，至V45時會減少至約1/2。由Hankinson's formula所得之n值為1.83-1.89。小試片之音速值表現與全板相同。破壞係數（MOR）會隨密度及用膠量之增加而增大，彈性係數（MOE）亦同。靜曲強度異方性：MOR（//／⊥）為4.54~5.02，MOE（//／⊥）為6.83~11.01，故定向效果極優良。MOR、MOE、動彈性係數（MOEd）各與音速值（V）間，均具極顯著之正相關。

關鍵字

杉木 ； 定向粒片板 ； 長薄片型粒片 ； 定向率 ； 音速

並列摘要

The purposes of this study were to investigate the flake alignment on the orthotropic properties of OSB, such as sound velocity and static bending strength. Furthermore, the relationships among the sound velocity, MOR and MOE due to the flake alignment were also discussed. The results were summarized as follows: 1. The grain direction of 2 / 3 of the total flakes was about 15° , showing good performance of OSB. 2. The sound velocity of OSB with grain direction parallel to the machine direction (V//) was 4586- 4632m /sec, and that perpendicular to the machine direction (V -⊥ ) was 1430 ~1565 m I sec. The ratio of (V// /V -⊥ ) was 2.93 ~3.24. The bending specimen had the same phenomenon. 3. The sound velocity decreased with increasing grain direction on the surface of OSB. 4. The n values derived from Hankinson's formula were 1.83 ~ 1.89. 5. The MOR and MOE increased with increasing the resin content and board density. The orthotropic property of MOR was 4.54 ~ 5.02, and that of MOE was 6.83 ~11.01. 6. The sound velocity was highly related with MOR and MOE and dynamic MOE.

並列關鍵字

China Fir ； Oriented strand board ； Flake alignment ； Sound velocity