密度與用膠量影響粒片板靜曲試驗之AE現象

Effects of Density and Resin Content on Accoustic Emission Events of Particleboard during Static Bending Test

黃國雄(Gwo-Shyong Hwang)

《台灣林業科學》 14卷1期 (1999/03) Pp. 29-35

https://doi.org/10.7075/TJFS.199903.0029

摘要

本研究之目的首先瞭解靜曲試驗時粒片板之密度與用膠量對AE發生之影響，進而利用AE技術推測粒片板靜曲強度。試驗中以不同密度與不同用膠量之條件分別製造粒片板，並於靜曲試驗時檢測AE之發生。由試驗結果得知粒片板之靜曲強度與靜曲彈性係數均隨板密度與用膠量之增加而明顯增大，然而，AE總數隨板密度與用膠量之增加而明顯減少。試驗結果亦顯示靜曲強度與靜曲彈性係數愈大者，AE總數愈少；其原因係密度較小或用膠量較低者，強度性質較差，於較低載重時容易發生微小破壞而產生較多之AE。無論是不同密度或是不同用膠量之粒片板，於靜曲試驗時之初期，AE總數達到一定值時之載重與靜曲強度之間，均具有良好之直線關係，顯示可由試驗初期AE總數達到一定值時之載重推測其靜曲強度。

關鍵字

粒片板 ； 靜曲試驗 ； 密度 ； 用膠量 ； 音射

並列摘要

The purpose of this study was to understand the effects of density and resin content on acoutic emissions (AE) generated from particleboard during static bending test. An estimation of the MOR of the particleboard was then conducted by utilizing the AE technique. Two groups of particleboard with different densities and resin contents, respectively, were tested for static bending strength; AE events were monitored simultaneously. MOR and MOE increased with increasing density and resin content of particleboard, however, cumulative AE events decreased with increasing density and resin content. Results also showed that higher MORs had fewer cumulative AE events. The reason is the weaker strength properties of particleboard with low density and low resin content; therefore, more AE events were generated with microfractures enlarged under an initial smaller load of the static bending test. For the 2 groups of particleboard with different densities or different resin contents, good linear correlations existed between the MOR and load when AE events approached a specified value in the early stage of the static bending test. It was possible to estimate the MOR by these loads.

並列關鍵字

particleboard ； static bending test ； density ； resin content ； accoustic emission